CT600 box-by-box guide: every box on the Company Tax Return explained

The CT600 is the Company Tax Return form filed with HMRC. Tax Optimiser completes it for you from the figures you enter in the Corp Tax workspace — the CT600 Boxes section of the calc screen shows exactly which boxes your figures populate, and each box there links to its entry below. Box numbering follows the CT600 (2026) form. For HMRC's own box-by-box notes see the Company Tax Return guide, on which this reference draws (Open Government Licence v3.0).

About this return

Boxes 30 and 35 — Period covered by this return

The start and end dates of the return period. A return can cover at most 12 months, so an accounting period longer than 12 months is split into two returns — Tax Optimiser does this automatically and shows Period 1 and Period 2 side by side. See Accounting periods longer than 12 months.

Box 40 — A repayment is due for this return period

Ticked when the return shows tax overpaid (box 605), for example after a loss carry-back or payable credit claim, or when there is a payable AVEC/VGEC to repay (box 886).

Box 45 — Claim or relief affecting an earlier period

Ticked when this return makes a claim that changes an earlier period — most commonly carrying a trading loss back to the previous year, or three years under terminal loss relief, from the Losses section. See Carrying back a trading loss.

Box 50 — Making more than one return now

Ticked when more than one return for the company is being delivered at the same time, as happens with a long period of account split into two returns.

Box 55 — This return contains estimated figures

Ticked when any figures are estimates to be revised later. Tax Optimiser sets this from the “contains estimates” flag on the General section.

Box 60 — Company part of a group that is not small

Ticked when the company is a member of a group that is not small — relevant to transfer pricing and senior accounting officer rules.

Box 65 — Notice of disclosable avoidance schemes

Ticked when the company must report a Disclosure of Tax Avoidance Schemes (DOTAS) reference — entered in the Tax Avoidance section, which also drives the CT600J supplementary page.

Box 70 — Compensating adjustment claimed

Transfer pricing: ticked when the company claims a compensating adjustment for a counterparty's transfer-pricing adjustment.

Box 75 — Company qualifies for SME exemption

Transfer pricing: ticked when the company relies on the small and medium-sized enterprise exemption from the transfer-pricing rules.

Boxes 80 to 90 — Accounts and computations

Box 80 confirms accounts and computations for this period are attached — Tax Optimiser always attaches your statutory accounts and its own computation, so box 80 is ticked on every return. Box 85 is used instead when the accounts cover a different period (for example the second return of a long period of account), and box 90 explains any accounts not attached.

Supplementary pages enclosed

Box 95 — CT600A, loans to participators

Ticked when the return includes the CT600A for loans by a close company to participators (directors/shareholders and their associates). Filled automatically when you enter loans in the Loan to Participators section.

Box 96 — CT600P, creative industries

Ticked when the return includes the CT600P for creative industry claims — driven by entries in the Creative Industries section.

Boxes 100 to 144 — other supplementary pages

One tick per supplementary page enclosed: CT600B controlled foreign companies and hybrid mismatches (box 100 — see the CT600B guide), CT600C group and consortium relief (105 — see the CT600C guide), CT600D insurance (110), CT600E charities and CASCs (115 — set by the Charity/CASC company type), CT600F tonnage tax (120), CT600G Northern Ireland (125), CT600H cross-border royalties (130), CT600I ring fence trades (135), CT600J disclosed avoidance schemes (140), CT600K restitution tax (141), CT600L Research and Development (142), CT600M freeports and investment zones (143) and CT600N Residential Property Developer Tax (144).

Turnover

Box 145 — Total turnover from trade

The turnover of the trade for the return period, from your Profit & Loss figures (apportioned by days when the period is split into two returns).

Box 150 — No recognised turnover

Ticked only by banks, building societies, insurance companies and other financial concerns that have no recognised turnover and so leave box 145 blank.

Income

Box 155 — Trading profits

The adjusted trading profit for tax: accounting profit plus disallowable expenses, less capital allowances and other adjustments. Tax Optimiser derives it from the P&L, Assets and adjustment sections — see the computation document for the full working.

Box 160 — Trading losses brought forward set against trading profits

Pre-April-2017 trading losses brought forward, which can only be used against profits of the same trade. Entered in the Losses section.

Box 165 — Net trading profits

Box 155 minus box 160. Calculated automatically.

Box 170 — Interest and profits from non-trading loan relationships

Bank and other interest receivable and other non-trading loan relationship credits, net of non-trading deficits — from the Non Trade Credit and Non Trade Debit sections.

Box 172 — Deficit carried back included in box 170

Ticked when box 170 is stated net of a non-trading deficit carried back from a later period.

Box 175 — Annual payments not otherwise charged

Annual payments received that are taxable but not caught by any other heading and from which Income Tax has not been deducted — for example payments under a covenant. Enter the full-period figure as Annual payments not otherwise charged on the Other Income section, and take the receipt out of the trade with an Income adjustment if it is in the accounts. See Other income on the CT600.

Box 180 — Non-exempt dividends from non-UK resident companies

Dividends and distributions from non-UK resident companies that do not fall into an exempt class. Most dividends are exempt and go in box 620 instead. Enter the gross figure on the Investment Income section; foreign tax on it is claimed on the Double Taxation Relief section. See Other income on the CT600.

Box 185 — Income from which Income Tax has been deducted

The gross amount of income received under deduction of Income Tax (for example patent royalties), when it is not included elsewhere on the return; the tax deducted itself is credited at box 515. Entered as Gross income taxed at source on the Income Tax Suffered section, per return period. Loan interest is box 170, not here. See Other income on the CT600.

Box 190 — Income from a property business

Net profit of a UK property business (rents less property costs). Mark the rental income and property expense lines as UK property in the P & L section; a net loss goes to box 805 instead and is relieved in box 250. See UK property income and losses.

Box 195 — Non-trading gains on intangible fixed assets

Net credits on intangible fixed assets (goodwill, trade marks, IP) held for a non-trading purpose. Entered on the Intangibles & Other Reliefs section. See Intangibles and other reliefs on the CT600.

Box 200 — Tonnage tax profits

Profits of a shipping company that has elected into the tonnage tax regime (with the CT600F).

Box 205 — Income not falling under any other heading

Miscellaneous taxable income that fits nowhere else on the form — entered in the Other Income section.

Chargeable gains

Box 210 — Gross chargeable gains

The total of the gains on disposals of capital assets in the period, before any losses. Enter each disposal on the Chargeable Gains section; the gain on each is calculated from its proceeds, cost, incidental costs and indexation. See Chargeable gains on the CT600.

Box 215 — Allowable losses

The capital losses set against the gains in box 210: this period’s losses first, then losses brought forward (entered as Capital losses brought forward on the Chargeable Gains section). Never more than box 210.

Box 220 — Net chargeable gains

Box 210 minus box 215. Calculated automatically and added to total profits in box 235. Unused capital losses carry forward and can only be set against future gains.

Profits before other deductions and reliefs

Box 225 — Losses brought forward against certain investment income

Pre-1 April 2017 trading losses brought forward and set against interest and dividends that would have been trading receipts (CTA 2010 s45(4)(b)) — for example a dealer’s investment income. Enter the claim as Pre-2017 loss claimed against investment income on the Losses section (it appears once there is a pre-2017 pool). It is capped at what is left of that pool after box 160 and at the income in boxes 170 to 185, and reduces the pool carried forward.

Box 230 — Non-trade deficits brought forward

Non-trading loan relationship deficits brought forward and set against non-trading profits of this period.

Box 235 — Profits before other deductions and reliefs

The net sum of boxes 165 to 205 (including 175 and 180) and 220, minus boxes 225 and 230. Calculated automatically.

Deductions and reliefs

Box 240 — Losses on unquoted shares

A loss on shares the company subscribed for in an unquoted qualifying trading company, claimed against income instead of only against gains (CTA 2010 s68). Enter it as Share loss claimed against income on the Chargeable Gains section and leave the disposal out of the disposals table. It is the first deduction, capped at the profits available; any part not relieved stays an allowable capital loss. See Chargeable gains on the CT600.

Box 245 — Management expenses

Expenses of managing a company’s investment business (CTA 2009 s1219), plus any excess management expenses brought forward. Enter the P&L figure on the Management Expenses section: it is taken out of the trading profit and relieved here, capped at the profits available. See Management expenses for investment companies.

Box 250 — UK property business losses

UK property business losses of this period (box 805) and any brought forward, set against total profits. Enter losses brought forward in the Losses section; the relief is calculated automatically and capped at the profits available. See UK property income and losses.

Box 255 — Capital allowances for management of the business

Capital allowances on assets used in managing the company’s investment business, relieved after box 245. Filled when Capital allowances claimed by on the Assets section is set to Investment business; unused allowances join the excess management expenses carried forward. See Management expenses for investment companies.

Box 260 — Non-trade deficits for this period

This period's non-trading loan relationship deficit claimed against total profits — from the Non Trade Debit section.

Box 263 — Carried forward non-trade deficits

Post-April-2017 non-trading deficits brought forward and claimed against total profits.

Box 265 — Non-trading losses on intangible fixed assets

A non-trading loss on intangible fixed assets set against total profits of the same period, when the company claims it (CTA 2009 s753). Enter the loss and tick Claim the loss against total profits of this period on the Intangibles & Other Reliefs section. It ranks after boxes 260 and 263 and is capped at the profits left; anything unrelieved is a non-trading debit of the next period. See Intangibles and other reliefs on the CT600.

Box 275 — Trading losses of this or a later period

Trading losses of this period (sideways relief) or of a later period (carry-back) set against total profits. Tax Optimiser fills this from the Losses section: the same-period set-off is automatic, and a loss brought back from a later period is entered in Trading Loss Brought Back — or written there for you when the later period applies its carry-back (see Carrying back a trading loss).

Box 280 — Amounts carried back from later periods

Ticked when box 275 includes a loss carried back from a later accounting period into this one.

Box 285 — Trading losses carried forward claimed against total profits

Post-April-2017 trading losses brought forward and claimed against total profits (rather than only trade profits).

Box 290 — Non-trade capital allowances

Capital allowances given against income other than a trade, property business or management expenses — for example special leasing of plant (CAA 2001 s260). Entered as a figure on the Intangibles & Other Reliefs section and capped at the profits left. See Intangibles and other reliefs on the CT600.

Box 295 — Total of deductions and reliefs

Total of boxes 240 to 275, 285 and 290. Calculated automatically.

Box 300 — Profits before qualifying donations and group relief

Box 235 minus box 295. Calculated automatically.

Box 305 — Qualifying donations

Qualifying charitable donations paid in the period, from the Donations section. Remember not to also disallow donations in the P&L — the relief is given here.

Box 310 — Group relief

Current-period losses surrendered by group or consortium companies and claimed against this company's profits. It equals C10 on the CT600C, entered on the Group Relief section, and can't exceed the profits left after box 305 — see the CT600C guide.

Box 312 — Group relief for carried forward losses

Group relief claimed for another group company's post-April-2017 carried-forward losses. It equals C130 on the CT600C (Part 3 of the Group Relief section) and ranks after box 310.

Box 315 — Profits chargeable to Corporation Tax

Box 300 minus boxes 305, 310 and 312 — the figure tax is charged on. Calculated automatically.

Box 320 — Ring fence profits included

Oil and gas ring fence profits included in box 315.

Box 325 — Northern Ireland profits included

Profits within the Northern Ireland Corporation Tax regime included in box 315.

Tax calculation

Boxes 326 to 328 — Associated companies

The number of associated companies in this period (326), or in each financial year (327/328) where the period spans two financial years with different limits. Associated companies share the small-profits and marginal-relief limits; set the count in the General section.

Box 329 — Small profits rate or marginal relief

Ticked when the company is chargeable at the small profits rate or entitled to marginal relief (periods ending after 31 March 2023). Tax Optimiser works this out from the rate bands applied.

Boxes 330 and 380 — Financial year

The financial year (starting 1 April) each row of the tax table relates to. A return period spanning 31 March uses both columns, and Tax Optimiser apportions profits between them by days automatically.

Boxes 335, 350, 365, 385, 400 and 415 — Amount of profit

The slice of chargeable profit taxed in that financial year at the rate alongside it. Calculated automatically from box 315.

Boxes 340, 355, 370, 390, 405 and 420 — Rate of tax

The Corporation Tax rate applied to that slice: the main rate, or the small profits rate where profits are within the lower limit.

Boxes 345, 360, 375, 395, 410 and 425 — Tax

Profit multiplied by rate for each row, in pounds and pence. Calculated automatically.

Box 430 — Corporation Tax

The total of the tax column (boxes 345, 360, 375, 395, 410 and 425). Calculated automatically.

Box 435 — Marginal relief

Marginal relief where profits fall between the lower and upper limits (from 1 April 2023: £50,000 and £250,000, apportioned for short periods and shared between associated companies). See the computation for the FY-by-FY working.

Box 440 — Corporation Tax chargeable

Box 430 minus box 435. Calculated automatically.

Reliefs and deductions in terms of tax

Box 445 — Community Investment Tax Relief

Tax relief for amounts invested in accredited community development finance institutions.

Box 450 — Double Taxation Relief

Credit for foreign tax paid on overseas income also taxed in the UK. Enter each source — the gross income and the foreign tax, up to the treaty rate — on the Double Taxation Relief section. The credit for each is the lower of the foreign tax and the UK tax on that income at the return’s average rate, and the total cannot exceed box 440 less box 445. See Double taxation relief on the CT600.

Box 455 — Underlying rate relief claim

Ticked when box 450 includes relief at the underlying rate on foreign dividends. Most foreign dividends are exempt for a UK company; Tax Optimiser does not make this claim and leaves the box blank.

Box 460 — Amount carried back from a later period

Ticked when box 450 includes double taxation relief carried back from a later period. Tax Optimiser does not make this claim and leaves the box blank.

Box 465 — Advance Corporation Tax

Surplus ACT set against the liability under the shadow ACT rules (legacy — pre-1999 distributions).

Box 470 — Total reliefs and deductions in terms of tax

Total of boxes 445, 450 and 465. Calculated automatically.

Coronavirus support schemes and overpayments

Boxes 471 to 474 — CJRS and other coronavirus overpayments

Box 471: CJRS/Job Support Scheme payments received in the period; box 472: the amount the company was actually entitled to; box 473: overpayments already assessed or disclosed; box 474: other coronavirus scheme overpayments. Any net overclaim becomes additional tax at box 526.

Energy levies

Boxes 986 and 987 — Energy (Oil and Gas) Profits Levy and Electricity Generator Levy

Box 986: amounts liable to the Energy (Oil and Gas) Profits Levy; box 987: exceptional generation receipts for the Electricity Generator Levy. Only relevant to oil and gas producers and electricity generators.

Calculation of tax outstanding or overpaid

Box 475 — Net Corporation Tax liability

Box 440 minus box 470. Calculated automatically.

Box 480 — Tax payable on loans to participators

The section 455 charge (33.75%) on loans to participators outstanding at year end, from the Loan to Participators section. Equals box A80 on the CT600A.

Box 485 — CT600A box A70 completed

Ticked when relief for loans repaid, released or written off (section 458) is claimed on the CT600A.

Boxes 490 to 502 — CFC tax, bank levy and other charges

Controlled Foreign Companies tax (490 — the total CFC charge from box B30 on the CT600B; see the CT600B guide), bank levy (495), bank surcharge (496), Residential Property Developer Tax (497), their total (500), Energy (Oil and Gas) Profits Levy payable (501) and Electricity Generator Levy payable (502). Rare for owner-managed companies.

Box 505 — Supplementary charge (ring fence trades)

The supplementary charge on oil and gas ring fence profits.

Box 510 — Tax chargeable

Total of boxes 475, 480, 500, 501, 502 and 505. Calculated automatically.

Box 515 — Income Tax deducted from gross income

Income Tax suffered at source on income included in profits (see box 185), credited against the Corporation Tax bill. From the Income Tax Suffered section.

Box 520 — Income Tax repayable to the company

Any excess of Income Tax suffered over the tax chargeable, repayable to the company.

Box 525 — Self-assessment of tax payable before restitution tax and coronavirus overpayments

Box 510 minus box 515. Calculated automatically.

Box 526 — Coronavirus overpayment now due

The net coronavirus support scheme overclaim now assessed through the return (boxes 471 + 474 minus 472 and 473).

Box 527 — Restitution tax

The 45% charge on interest awarded on restitution claims against HMRC (with the CT600K).

Box 528 — Self-assessment of tax payable

Total of boxes 525, 526 and 527 — the headline self-assessed liability for the return.

Tax reconciliation

Box 530 — Research and Development credit

R&D tax credit set against the liability, from the R&D Expenditure section (with the CT600L).

Box 540 — Creatives tax credit

Payable creative industry tax credits (film, TV, video games and the cultural reliefs) set against the liability.

Box 541 — Audio-Visual and Video Games expenditure credit

AVEC/VGEC (the expenditure credits replacing the old creative reliefs) set against the liability, from the Creative Industries section.

Box 545 — Total R&D, creatives and AVEC/VGEC credits

Total of boxes 530 to 541. Calculated automatically.

Boxes 550 to 565 — Land remediation, life assurance and first-year tax credits

Land remediation tax credit (550), life assurance company tax credit (555), their total (560) and capital allowances first-year tax credit (565).

Boxes 570 to 580 — Credits payable

The parts of the credits above that exceed the liability and become payable to the company: surplus R&D and creatives credits (570), land remediation or life assurance credit (575) and first-year tax credit (580). Calculated automatically.

Boxes 585 to 590 — Ring fence and Northern Ireland amounts included

Memorandum boxes: ring fence Corporation Tax (585), Northern Ireland Corporation Tax (586) and ring fence supplementary charge (590) included in the liability.

Box 595 — Tax already paid (and not already repaid)

Corporation Tax for this period already paid to HMRC, for example quarterly instalments or early payments.

Box 600 — Tax outstanding

Box 525 minus boxes 545, 560, 565 and 595 — what remains to pay. Calculated automatically.

Box 605 — Tax overpaid

The excess where credits and tax already paid exceed the liability — this drives the repayment claim (boxes 865 onwards) and ticks box 40. Full guide: CT600 repayments, box by box.

Boxes 610 to 615 — Amounts surrendered to this company

Group tax refunds (610), AVEC/VGEC (614) and R&D expenditure credits (615) surrendered to this company by other group members.

Exporter information

Boxes 616 to 618 — Exports

Whether the company exported goods (616), services (617) or neither (618) outside the UK during the period. Answer Did the company export in this period? on the General section

Whether the company exported goods (616), services (617) or neither (618) outside the UK during the period. Informational only.

mdash; Goods and Services can both be selected; Neither clears them. The submission wizard warns if the question is unanswered.

Indicators and information

Box 620 — Franked investment income / exempt ABGH distributions

Exempt distributions received from non-group companies — historically used for the marginal relief limits. From the Investment Income section.

Box 625 — Number of 51% group companies

The number of related 51% group companies, which divides the quarterly instalment thresholds. Set in the General section.

Boxes 630 and 631 — Instalment payments

Ticked when the company should have paid by quarterly instalments as a large company (630, augmented profits over £1.5m) or very large company (631, over £20m) — whether or not it actually did. Only one of the two is ever ticked. Tax Optimiser ticks them automatically: augmented profits are the profits chargeable (box 315) plus exempt distributions received (box 620), and the limits are divided by the box 625 count plus one and reduced for a period shorter than twelve months. Answer Is first year and not large? on the General section when the company was not large in the previous twelve months and its profits are under £10m — that raises the large-company limit to £10m for the year. When either box is ticked the General section shows a warning, because the instalments themselves are not calculated. See HMRC’s guide to paying Corporation Tax in instalments.

Box 635 — Group payments arrangement

Ticked when the company is within an HMRC group payment arrangement for the period — the flag on the General section.

Box 640 — Intangible assets written down or sold

Ticked when the company wrote down or disposed of intangible fixed assets in the period.

Box 645 — Cross-border royalty payments

Ticked when the company made cross-border royalty payments (see also the CT600H).

Box 647 — Eat Out to Help Out

Reimbursed Eat Out to Help Out discounts included as taxable income (August 2020 scheme).

Enhanced expenditure and tax reliefs

Boxes 650 to 658 — R&D and creatives claim indicators

Who is claiming and what has been filed: SME claim (650), R&D intensive SME (653), large company claim (655), and confirmations that the R&D claim notification form (656), R&D additional information form (657) or creatives additional information form (658) have been submitted to HMRC. The information forms are mandatory — HMRC removes R&D claims made without them.

Box 659 — R&D qualifying expenditure (SME)

The qualifying expenditure behind an SME or R&D-intensive-SME claim, required for periods starting on or after 1 April 2023.

Box 660 — R&D enhanced expenditure

The enhanced (uplifted) R&D expenditure figure from the R&D Expenditure section.

Box 663 — Creatives core expenditure

Core expenditure behind a creative industries claim, from the Creative Industries section.

Box 665 — Creatives additional deduction

The additional deduction given by the creative industry reliefs.

Box 670 — Total enhanced expenditure

Box 660 plus box 665. Calculated automatically.

Boxes 675 and 680 — Subcontracted R&D and vaccine research

R&D enhanced expenditure of an SME on work subcontracted to it by a large company (675) and vaccine research expenditure (680, legacy).

Box 685 — Land remediation enhanced expenditure

The 150% enhanced deduction for qualifying land remediation expenditure.

Capital allowances - in trading profits

Boxes 688 to 730 — Allowances and charges in trading profits

Memorandum boxes analysing the capital allowances and balancing charges already reflected in the trading profit: full expensing (688/689), annual investment allowance (690), super-deduction (691/692), special rate 50% first-year allowance (693/694), special rate pool (695/700), main pool (705/710), structures and buildings (711), electric vehicle charge-points (713/714), business premises renovation (715/720), enterprise zones (721/722), zero-emission goods vehicles (723/724), zero-emission cars (726/727) and other (725/730). Tax Optimiser fills these boxes from the Assets section: AIA in 690, full expensing in 688, super-deduction in 691, the 50% special rate FYA in 693, the special rate pool (695) and main pool (705) totals — each including the AIA allocated to that pool and its writing-down allowance — the pool balancing charges in 700 and 710, structures and buildings in 711, and the 100% first-year allowances on electric vehicle charge-points (713, the Electric Vehicle Charge-Point asset type), zero-emission goods vehicles such as electric vans (723, the Zero-Emission Goods Vehicle asset type — see Electric vans and zero-emission goods vehicles) and zero-emission cars (726, the Energy Efficient Cars asset type) — all taken out of the main pool figure in 705. Where the box has been withdrawn for the period, the allowance stays in 705. Several first-year allowances have been withdrawn and their boxes retire by accounting-period start date: enterprise zones from 1 April 2024, zero-emission goods vehicles from 1 April 2025, and electric vehicle charge-points and zero-emission cars from 1 April 2026.

Capital allowances - not in trading profits

Boxes 733 to 755 — Allowances and charges not in trading profits

The same analysis for allowances on assets outside the trade (for example a property business or managed investments): full expensing (733/734), AIA (735), structures and buildings (736), EV charge-points (737/738), business premises renovation (740/745), super-deduction (741/742), special rate allowance (743/744), enterprise zones (746/747), zero-emission goods vehicles (748/749), zero-emission cars (751/752) and other (750/755). Tax Optimiser fills these boxes instead of 688–730 when the period's capital allowances belong to a UK property business or to the company’s investment business (Assets section, Capital allowances claimed by; the investment business’s allowances are relieved in box 255): AIA in 735, full expensing in 733, structures and buildings in 736, super-deduction in 741, the 50% special rate FYA in 743, the 100% first-year allowances on EV charge-points in 737, zero-emission goods vehicles in 748 and zero-emission cars in 751, the remaining pool allowances in 750 and pool balancing charges in 755.

Qualifying expenditure

Boxes 760 to 775 — Qualifying expenditure

The expenditure incurred in the period on which allowances are claimed: machinery and plant with first-year allowance (760), designated environmentally friendly plant (765), long-life assets and integral features (770), structures and buildings (771), super-deduction plant (772), special rate allowance plant (773) and other machinery and plant (775).

Losses, deficits and excess amounts

Boxes 780 and 785 — Trading losses (UK)

The trading loss arising in this period for trades carried on wholly or partly in the UK (780) and the maximum available to surrender as group relief (785). Tax Optimiser reports the loss arising from your figures; how it is used (carry back, carry forward, sideways) is set in the Losses section.

Box 790 — Trading losses (wholly outside the UK)

Losses of trades carried on wholly outside the UK, which can only be carried forward against the same trade.

Boxes 795 and 800 — Non-trade deficits

The non-trading loan relationship deficit arising (795) and the maximum available for group relief surrender (800).

Boxes 805 and 810 — UK property business losses

The UK property business loss arising (805) and the maximum available for group relief surrender (810). Tax Optimiser reports the loss arising from the P & L lines marked UK property; it is set against total profits in box 250 automatically and any balance carries forward (see the Losses section and UK property income and losses).

Boxes 815 to 825 — Other losses

Overseas property business losses (815), losses from miscellaneous transactions (820) and capital losses (825) arising in the period. Tax Optimiser fills box 825 from the Chargeable Gains section: the whole capital loss arising, whether or not it was set against the period’s gains in box 215.

Boxes 830 and 835 — Non-trading losses on intangibles

The non-trading intangibles loss arising (830) and the maximum available for group relief surrender (835). Tax Optimiser fills box 830 from the Intangibles & Other Reliefs section, whether or not the loss is claimed in box 265; box 835 is not filled.

Boxes 840 to 855 — Excess amounts

Amounts unrelievable in this period that could be surrendered as group relief: excess non-trade capital allowances (840), excess qualifying donations (845) and excess management expenses (850 arising / 855 surrenderable). Tax Optimiser fills box 850 from the Management Expenses section: this period’s management expenses, including capital allowances for management, that could not be relieved (more). Box 855 is not filled.

Northern Ireland information

Boxes 856 to 858 — NI group relief analysis

Only for companies in the Northern Ireland regime: group relief claimed for NI trading losses used against rest-of-UK profits (856), NI losses against NI profits (857) and rest-of-UK losses against NI profits (858).

Overpayments and repayments

Box 860 — Do not repay sums of this amount or less

An optional de-minimis: HMRC will hold rather than repay overpayments at or below the figure entered.

Boxes 865 to 895 — Repayments claimed for this period

How the box 605 overpayment is claimed: repayment of Corporation Tax (865), repayment of Income Tax (870), payable R&D tax credit (875), payable R&D expenditure credit (880), payable creatives credit (885), payable AVEC/VGEC (886), payable land remediation or life assurance credit (890) and payable first-year tax credit (895, closed for periods starting after 31 March 2020). Tax Optimiser derives these from the payable credits on the return, with box 865 as the remaining balance. Full guide: CT600 repayments, box by box.

Boxes 900 to 915 — Surrender of tax refund within the group

To surrender a refund to another group company: the amount surrendered (900), whether the joint notice is attached (905) or will follow (910), and any amount whose repayment should be held until the notice arrives (915).

Bank details and nominated payee

Boxes 920 to 940 — Bank details

Where any repayment should be sent: bank or building society name (920), branch sort code (925), account number (930), account name (935) and building society reference (940). Entered on the Repayments section of the Corp Tax workspace — see CT600 repayments, box by box.

Box 943 — R&D payable credit condition

Ticked when an R&D payable credit is claimed and one of the conditions listed in HMRC's guide applies to the nominee arrangements.

Boxes 945 to 970 — Payments to a person other than the company

The authority to pay a repayment to a nominee instead of the company: the status of the person giving authority (945), the company name (950), the nominee's name (955) and address (960), the nominee reference (965) and the recipient name (970). Leave blank to have repayments paid to the company.

Declaration

Boxes 975 to 985 — Declaration

The name (975), date (980) and status (985) of the person declaring the return is correct and complete — in Tax Optimiser, the accepting director chosen on the Send Tax Return step.