A Yeovil bookkeeper offering accounting & bookkeeping services for Sherborne, Langport, Somerton, Wincanton and surrounding areas of South Somerset and West Dorset.

Corporation Tax

Using corporation tax rates in force during the chosen tax year

NOTE: To reduce data entry error some fields shaded blue are disabled until a value is entered in main box above them.

    Please enter the tax year whose rates apply to the company's period of trading:

£ Enter the number of months in your accounting period. (Usually this is 12).
£ Enter the number of associated companies excluding this company (if you have no associated companies, enter '0').

Based on the above the Marginal Relief Lower Limit is:  £  And the Upper Limit is:  £

£ Enter trading profit for the tax period here.
£ Add: disallowable trading expenses including depreciation.      List of disallowed expenses
£ Less: capital allowances claimed.      Summary of capital allowances available
£ Less: value of any trading loss b/f from last tax year or property losses relieved against trading profit.
£ Add: value of any trading loss incurred c/f to next period, relieved against other income this tax year or carried back against profits from the last period.

£Enter property income for the tax period. (Exclude any rent paid to cover expenses normally paid by tenants.)
£ Less: allowable expenses.      Summary of allowable property expenses

Tick this box if you are claiming Wear and Tear Allowance (furnished accommodation only).

£ Less: any property losses b/f from last tax year or trading losses relieved against property income.
£ Add: any property losses offset against other income this period or c/f to next period.

£ Enter net amount of any bank or building society interest received during the tax period from which income tax was deducted at source. (Don't include basic rate income tax deducted at source).

£ Enter value of interest received gross. (Normally companies receive their interest income gross.)
£ Less: gross value of interest payable on account balances during the period.

£ Enter value of dividends received during the tax period. Do not include the 10% tax credit.

£ Enter value of contributions to any approved pension plans for company employees or to Gift Aid during the tax period.

£ Enter chargeable capital gains acquired during the tax period.

£ Less: capital losses b/f from previous period
£ Add: capital losses c/f to next period


Total Corporation Tax liability comes to:

£   Total Profits chargeable to Corporation Tax (including tax deducted at source)
£   Augmented Profits (taxable profits plus gross dividends)
£   Tax band allocation of augmented profits
£   Applicable Corporation tax rate
£   Corporation Tax Payable before reliefs
£   Less: Marginal Relief (if applicable)
£    Less: any income tax deducted at source on savings income (offset against CT under s.967 Corporation Tax Act 2010)


This Corporation Tax calculator is intended only for use where companies have relatively simple tax affairs and are able to submit their self-assessment using the short form CT600.

If Corporation Tax has been paid in advance, or if Corporation Tax is owing from a previous accounting period, then the amount payable given by this calculator will require appropriate adjustment downwards or upwards respectively.

Corporation tax periods cannot be longer than 12 months. If you have a longer accounting period you must split it into two tax periods: the first tax period is the twelve months beginning at the start of your accounting period: the second tax period comprises the remaining period at the end of your accounting period. Income and expenses must be apportioned appropriately between the periods and the tax liability calculated separately for each period.

Associated companies are those in which one company has a controlling interest in the other, or which are both controlled by a a third company. Control usually occurs where one company owns more than 50% of the shares of the other, or has more than half the voting rights. If there are no associated companies then a figure '0' must be entered into the designated box. If these is one other associated company then a figure '1' must be entered in this box and so on.

The correct figure for capital allowances must be entered against trading profit otherwise the calculated tax liability will be incorrect. Capital allowances available are subject to annual revision.

The correct amount of trading loss or property loss brought forward from a previous tax year must be entered in the designated boxes otherwise the tax calculation will be incorrect

The value of Wear and Tear allowance against property income is calculated from the figure in the main Property Income box. This value should not include any rent to cover expenses such as council tax or utilities that are normally paid by the tenant rather than the landlord. If such rent is included in the main box figure, then the value of Wear and Tear Allowance calculated will be too high.

Interest income received by companies is not usually subject to deduction of income tax at source. In this case the interest income must be inserted in the box marked for interest received gross. Bank or investment interest must be separated into that received gross and that received with basic rate tax deducted at source.The two categories of interest must be entered separately into two different boxes designated for these categories, otherwise the calculation of tax liability will be incorrect

The value of dividends received entered in the dividends box must be the amount actually received. If a gross figure with the tax credit included is entered in this box then the tax liability will be overestimated. Dividends are not taxable income for Corporation Tax, but they affect the tax rate when the company's taxable profits fall within the marginal relief band (currently between £300k and £1,500k for a company with no associated companies and a 12 month tax period).

Capital gains chargeable to Corporation Tax include gains on sale of shares in other companies as well as gains in the value of fixed assets such as buildings. Capital gains chargeable to companies are reduced by an indexation allowance which takes account of the general increase in prices over the period of ownership. Other capital gains may be subject to 'Rollover Relief' in which the gain is postponed by being reinvested in a new capital asset. Some assets such as cars or other mechancial devices with a limited useful life are exempt from capital gains tax. Chargeable capital gains for a period must be correctly calculated in order to obtain a correct calculation of Corporation Tax liability.

Capital losses may not be relieved against other types of income but should be offset against capital gains or carried forward to relieve against capital gains of a future period.

Trading losses and property losses may be relieved against other types of income in the same period. The amount of other income available is not reduced on account of Gift Aid donations.

Some companies trading in the offshore oil industry qualify for a lower Main Rate of Corporation Tax. This calculator cannot be used to estimate tax liabilities for these companies nor for any company which owns a controlling interest in one of them.

Rounding of values in the software algorithms may cause the tax payable to differ by a few pence from alternative computations using the same input figures.

This calculator should not be used to calculate tax for any other tax year than those available in the tax year pulldown menu.

This calculator requires correct input figures in order to generate a correct tax liability

This calculator is only intended to give a calculation of Corporation Tax subject to the above conditions. Four Elms Bookkeeping accepts no liability for the use of output generated by this calculator.

For help with tax calculations or tax returns contact Four Elms Bookkeeping on 01935 850807.

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