## Documentation Index

Access the complete documentation index at:
https://www.zoho.com/uk/books/help/llms.txt

Use this file to discover all available documentation pages before proceeding.

# Self Assessment

**Note:** Self Assessment is available in all the plans of Zoho Books.

**Note:**

This feature is available only for organisations with business type set as **Sole Trader** or **Limited Companies**.

Self Assessment is the system HMRC uses to collect income tax that is not deducted at source through PAYE (Pay As You Earn). If you are a sole trader, a landlord with rental income, a company director, or you have other untaxed income such as dividends or foreign earnings, you must file a Self Assessment tax return (SA100) each year to report your income, claim allowable expenses and reliefs, and settle your tax liability.

With Zoho Books you can generate and fill in the SA100 main return along with the following supplementary forms:

*   Employment
*   Self-Employment
*   UK Property
*   Tax Calculation

Once you fill in the required forms, you can get the return approved within your organisation, and submit it directly to HMRC.

**Warning:**

If you have any additional income sources that are not covered by the supported forms listed above, you will not be able to file your Self Assessment return using Zoho Books.

## Points to Remember

*   You can use the [HMRC Self Assessment checker](https://www.gov.uk/check-if-you-need-tax-return) to verify whether you need to file an SA100 return.
*   Self Assessment applies to individuals with qualifying income below the current MTD for Income Tax threshold. If your qualifying income exceeds the threshold, you must use [Making Tax Digital (MTD) for Income Tax](/uk/books/help/mtd-it/making-tax-digital.html) instead. These thresholds are set by HMRC and may change in future tax years.
*   You can currently generate Self Assessment returns only for the 2025–26 tax year (April 6, 2025 to April 5, 2026).
*   The deadline to submit your online return and make payment is **31 January** following the end of the tax year.

**Note:**

It is recommended to get your figures verified by an accountant before submitting your return to HMRC. The Zoho Books support team can help with product-related queries but cannot advise on tax calculations or provide tax guidance.

## Forms Supported in Zoho Books

Self Assessment consists of a main return form and a set of supplementary forms. Each supplementary form covers a specific type of income. Zoho Books currently supports the following forms:

Form

Name

Purpose

SA100

Self Assessment (Main) Tax Return

Consolidates all income, allowances, and adjustments to calculate your final tax position.

SA102

Employment

Reports salary, benefits, and pensions from employment along with PAYE tax already deducted.

SA103S

Self-Employment (Short)

Reports business income and allowable expenses for self-employed individuals with simpler accounts.

SA105

UK property

Reports rental income from UK property and captures allowable expenses to calculate property profit or loss.

SA110

Tax Calculation

Summarises the net tax due or refund owed, including Class 2 and Class 4 NICs, and Student Loan and Postgraduate Loan repayments.

SA302

Tax Breakdown Summary

Shows how your tax is calculated and the components involved. This form is for your reference only and is not submitted to HMRC.

* * *

## Generate Self Assessment Return

**Note:**

The _Self Assessment_ module is available by default under _Filing & Compliance_ for **Sole Trader** or **Limited Companies** businesses.

To generate a Self Assessment return:

*   Go to _Filing & Compliance_ on the left sidebar and select **Self Assessment**.
*   Click **Generate Self Assessment Return** in the top right corner.
*   In the _Generate Self Assessment Return_ pop-up, enter the **Start Date** and **End Date** for the tax year.
*   Click **Generate**.

![Generate Self Assessment Return](/uk/books/help/images/self-assessment/generate-sar.png)

### Map Accounts (Sole Traders Only)

**Note:**

This step applies only to Sole Trader organisations.

In the _Map Accounts_ tab, you can assign the accounts from your chart of accounts to the relevant sections of the SA103S form. This mapping determines which accounts feed into the business income and allowable expense figures on the return.

Here’s how:

*   Go to _Filing & Compliance_ in the left sidebar and select **Self Assessment**.
*   Under each section (**Self Employment Business Income** and **Self Employment Allowable Expenses**), click **\+ Add Accounts** to map the relevant accounts.
*   Click **Next**.

![Map Accounts](/uk/books/help/images/self-assessment/map-accounts.png)

You will be redirected to the _Forms_ tab.

### Forms

The _Forms_ tab displays all the forms: **SA100**, **Employment**, **Self-Employment Short**, **UK Property**, **Tax Calculation**, and **Tax Breakdown Summary**. You can navigate to the relevant form tab and fill in the required details.

#### Self Assessment Tax Return - SA100 form

The SA100 is the main Self Assessment tax return. It brings together your total income, tax reliefs, allowances, and adjustments for the tax year to determine your final tax position. Every individual filing a Self Assessment must complete this form.

In Zoho Books, the SA100 form is organised into the following sections:

Section

Description

Your personal details

Name, date of birth, phone number, Unique Taxpayer Reference (UTR), taxpayer status, and National Insurance number.

Income

Dividends and interest from UK banks and building societies, UK pensions, annuities and other state benefits received, and other UK income not included on supplementary pages.

Tax Reliefs

Payments into registered pension schemes, charitable giving, and Blind Person’s Allowance.

Student Loan and Postgraduate Loan repayments

Student Loan and Postgraduate Loan details, including the loan type, repayment plan, and deductions taken by your employer.

High Income Child Benefit Charge

Total Child Benefit received, the number of children, and the date payments stopped (if applicable).

Winter Fuel Payment

Winter Fuel Payment (WFP) and Pension Age Winter Heating Payment (PAWHP) amounts.

Marriage Allowance

Details about transferring or receiving marriage allowance, including your spouse or civil partner’s personal information.

Finishing your tax return

Tax refunded or set off, underpaid tax, overpaid tax, any other information, and declaration.

Enable the toggle for the sections that apply to you and enter the relevant details.

#### Employment - SA102 form

The SA102 form captures details of your employment income. If you have employment income to report, enable the toggle next to **Do you need to fill out this Employment form?**, and enter the relevant details.

The form is organised into the following sections:

Section

Description

Employment income

Pay from this employment, payrolled benefits that affect your student loan repayments, UK tax taken off pay, tips and other payments not on your P60, PAYE tax reference of your employer, your employer’s name, whether you were a company director, close company details, and whether the employment income is from inside off-payroll working engagements.

Class 4 National Insurance maximum charge

Earnings for Class 1 from P60, used to calculate the correct Class 4 NIC liability if you are both self-employed and employed.

Benefits from your employment

Benefits received from your employment, as reported on your form P11D (or equivalent information).

Employment expenses

Business expenses you paid yourself while doing your job.

#### Self-Employment (short) - SA103S form

The SA103S form is the short version of the Self-Employment supplementary pages. If you have self-employment income to report, enable the toggle next to **Do you need to fill out the Self Employment section?**, and enter the relevant details. The Business income and Allowable business expenses will be auto-populated for sole traders. The form is organised into the following sections:

Section

Description

Business Details

Your business description, postcode, whether your business started or ceased during the tax year, the date your books are made up to, and whether you used traditional accounting or cash basis.

Business income

Your turnover (takings, fees, sales, or money earned), any other business income, and the trading income allowance.

Allowable business expenses

Deductible expenses including cost of goods, car and travel expenses, wages, rent, repairs, accountancy fees, interest charges, office costs, and other allowable expenses.

Net profit or loss

The net profit or net loss calculated from your income and expenses.

Capital allowances

Annual Investment Allowance, zero-emission car allowance, other capital allowances, Structures and Buildings Allowance, and total balancing charges.

Calculating your taxable profit

Net business profit for tax purposes, factoring in goods or services for personal use, losses brought forward from earlier years, and any other business income.

Total taxable profits or net business loss

The total taxable profits from your business or the net business loss for tax purposes.

Losses, Class 2 and Class 4 NICs and CIS deductions

Losses set off against other income, losses to be carried back or forward, Class 2 NICs voluntary payment options, Class 4 NICs exemptions, and Construction Industry Scheme (CIS) deductions.

#### UK Property - SA105 form

The UK Property form (SA105) captures details of your UK property income. If you have UK property income to report, enable the toggle next to **Do you need to fill out the UK Property section?**, and enter the relevant details.

The form is organised into the following sections:

Section

Description

UK property details

Number of properties rented out, whether property income ceased during the tax year, whether income is from property let jointly, and Rent a Room relief eligibility.

Property income

Total rents and other income from property, property income allowance, whether traditional accounting or cash basis is used, tax taken off property income, premiums for the grant of a lease, and reverse premiums and inducements.

Property expenses

Rent, rates, insurance and ground rents, property repairs and maintenance, finance costs (including mortgage interest), legal and professional costs, cost of services provided, and other allowable property expenses.

Calculating your taxable profit or loss

Adjusted profit for the year, losses brought forward from previous years, and taxable profit or loss after all adjustments.

#### Tax Calculation - SA110 form

The SA110 form provides a summary of the tax calculation for the return period. You can also add adjustments to the return if any. It is organised into the following sections:

Section

Description

Tax and National Insurance due

Total tax due or overpaid, Class 2 NICs, and Class 4 NICs due, Student Loan and Postgraduate Loan repayments.

Underpaid tax and other debts

Any underpaid tax for earlier years or the current year included in your tax code, as well as outstanding debts.

Payments on account

Claim to reduce payments on account for the next tax year and enter your first payment on account amount.

Blind person’s surplus allowance and married couple’s surplus allowance

Any surplus allowances available.

Adjustments to tax due

Increases or decreases in tax due because of adjustments to earlier years, and any next tax year repayment being claimed.

Payments on Account Paid (This Year)

First and second payments on account made already for the current tax year (31 January and 31 July).

#### Tax Breakdown Summary - SA302 form

The Tax Breakdown Summary (SA302) provides a high-level breakdown of your tax calculation, showing your total income, Personal Allowance, taxable income, tax due after reliefs, any adjustments, and the final balancing payment or refund. It is for your reference only and is not submitted to HMRC.

Once you’ve filled in and reviewed the required forms, click **Save and Generate**.

In the confirmation pop-up, read the terms and click **Finalise Return**.

![Save and Generate](/uk/books/help/images/self-assessment/save-sar.png)

The Self Assessment return will be generated.

* * *

## Approve a Self Assessment Return

Once you’ve generated the return, the admins in your organisation can review and approve it. To do this, your admins should:

*   Go to _Filing & Compliance_ in the left sidebar and select **Self Assessment**.
*   Select the return they want to approve.
*   In the _Self Assessment_ page, click **Approve Return**.

![Approve Return](/uk/books/help/images/self-assessment/approve-sar.png)

*   In the confirmation pop-up, click **Approve Now**.

The Self Assessment return will be approved.

### Revoke Approval

To revoke the approval for a Self Assessment return you had already approved:

*   Go to _Filing & Compliance_ in the left sidebar and select **Self Assessment**.
*   Select the return for which you want to revoke approval.
*   In the _Self Assessment_ page, click the **More** icon in the top right corner, and select **Revoke Approval** from the dropdown.

![Revoke Approval](/uk/books/help/images/self-assessment/revoke-approval.png)

*   In the _Reason for Revoking Approval_ pop-up, enter the reason to revoke approval.
*   Click **Submit**.

The approval for the return will be revoked.

* * *

## Submit a Self Assessment Return to HMRC

Once an admin has approved the return, you can directly submit the return from your Zoho Books organisation. Here’s how:

*   Go to _Filing & Compliance_ in the left sidebar and select **Self Assessment**.
*   Select the return you want to submit to HMRC.
*   In the _Self Assessment_ page, click **Submit to HMRC**.

![Submit to HMRC](/uk/books/help/images/self-assessment/submit-sar.png)

*   In the _Submit to HMRC_ pop-up, fill in the following details:
    *   **Government Gateway User ID:** Enter the user ID you use to sign in to your HMRC online account.
    *   **Password:** Enter the password associated with the above user ID.
    *   Read and agree to the terms and click **Submit**.

![Submit to HMRC Pop-up](/uk/books/help/images/self-assessment/submit-pop-up.png)

The Self Assessment return will be submitted to HMRC.

**Note:**

You can start submitting your Self Assessment tax return once the respective tax year ends on 6 April. The deadline to submit your online return and make payment to HMRC is **31 January** following the end of the tax year. For example, for the 2025–26 tax year, the return must be submitted and payment made on or before 31 January 2027.

### Submission Status

Once you submit the Self Assessment return to HMRC, the return will go through different statuses based on HMRC’s response:

Status

Description

**Filing in Progress**

The return has been sent and is being processed by HMRC.

**Filed**

HMRC has successfully received and accepted the return. A **Document Reference No** and **IRMark** will be displayed for your records.

**Filing Failed**

The submission was not accepted by HMRC. Click **View Errors** to check what went wrong, [edit](/uk/books/help/self-assessment.html#Edit-Return) the return to fix the issues, and [resubmit](/uk/books/help/self-assessment.html#Submit-to-HMRC) it. Refer to [Understanding HMRC Error Codes](/uk/books/help/self-assessment.html#HMRC-Error-Codes) for a list of error codes and the forms they relate to.

Here’s how the status appears once HMRC has accepted the return:

![Filing Successful](/uk/books/help/images/self-assessment/filing-success.png)

Make sure to note down the **IRMark** and **Document Reference No** for your records, as you may need them for future correspondence with HMRC.

Here’s how the status appears if your return submission to HMRC has failed:

![Filing Failed](/uk/books/help/images/self-assessment/filing-failed.png)

Click **View Errors** to see what went wrong and fix the issues before resubmitting.

* * *

### Understanding HMRC Error Codes

When you submit your Self Assessment return to HMRC, the submission may sometimes be rejected with error codes. The following codes help you identify the form that needs correction.

**Error Codes**

Error Code

Description

**EMP**

Refers to the Employment form (SA102).

**SSE**

Refers to the Short Self-employment form (SA103S).

**CAL**

Refers to the Tax Calculation Summary form (SA110).

**PRO**

Refers to the Income from Property form (SA105).

**Insight:**

HMRC may return multiple errors in a single rejection. Address all listed errors before submitting it again to avoid repeated rejections.

* * *

## Self Assessment Returns - Operations

### Edit a Self Assessment Return

**Note:**

If the return has been approved, you must first [revoke the approval](/uk/books/help/self-assessment.html#Revoke-Approval), then edit the return to make the required changes, and [re-approve](/uk/books/help/self-assessment.html#Approve-Return) it once the changes are complete.

To edit a Self Assessment return:

*   Go to _Filing & Compliance_ in the left sidebar and select **Self Assessment**.
*   Select the return you want to edit.
*   In the _Self Assessment_ page, click the **More** icon in the top right corner, and select **Edit**.

![Edit Self Assessment Return](/uk/books/help/images/self-assessment/edit-sar.png)

*   In the confirmation pop-up, click **Continue to Edit**.
*   In the _Generate Self Assessment Return_ page, follow the same process as generating the return. If you are a sole trader, map accounts and review forms. If you are a limited company, review forms directly.

The Self Assessment return will be updated.

### Delete a Self Assessment Return

**Note:**

To delete an approved return, you must [revoke the approval](/uk/books/help/self-assessment.html#Revoke-Approval) first.

To delete the return you had generated:

*   Go to _Filing & Compliance_ in the left sidebar and select **Self Assessment**.
*   Select the return you want to delete.
*   In the _Self Assessment_ page, click the **More** icon in the top right corner, and select **Delete**.

![Delete Self Assessment Return](/uk/books/help/images/self-assessment/delete-sar.png)

*   In the confirmation pop-up, click **Delete** again.

The return will be deleted.

**Note:**

You cannot delete a return in the **Filed** status.