Self Assessment Tax Returns in Bournemouth: Prepare Early and Avoid Last-Minute Problems

Self Assessment is the system used by HM Revenue & Customs to collect Income Tax from people and businesses whose income is not always fully taxed before they receive it. A return is completed after the end of the relevant tax year, and anyone asked by HM Revenue & Customs to submit one must do so.

Income Tax is normally deducted automatically from wages and pensions. However, income from self-employment, property, investments or other sources may need to be reported separately.

Not everyone with additional income will have exactly the same reporting requirement. The position depends on the source, amount and tax year concerned.

Being a company director does not, by itself, determine every person's filing position. What matters is the individual's income, gains, reliefs, reporting requirements and whether HM Revenue & Customs has issued a notice to file.

If you are unsure, do not assume that no return is required. Check the current Self Assessment guidance on GOV.UK or ask an accountant to review your circumstances.

If you register after 5 October 2026, HM Revenue & Customs says it will send you a letter or email giving a filing deadline three months from the date of that communication. Any tax due for 2025/26 must still normally be paid by 11:59pm on 31 January 2027.

Check the latest official Self Assessment deadline page before acting, especially if your return is late, you have received a letter or your circumstances are unusual.

Late submission or late payment can result in penalties or interest. HM Revenue & Customs states that a person may have to pay interest and a penalty if they do not file and pay on time.

If a deadline has already passed, avoiding the issue will not solve it. Gather your information, establish what remains outstanding and take action as soon as possible.

Do not delay filing solely because you are concerned about paying the full amount. Filing and payment are related but separate responsibilities. You should obtain appropriate guidance about both.

Sole traders and partners must keep records of business income and expenses for their Self Assessment returns, as well as relevant records of personal income.

You do not normally send all expense evidence with the return, but HM Revenue & Customs says you should retain accurate proof and records in case they are requested.

A sole trader can deduct allowable business expenses when working out taxable profit. Personal withdrawals from the business are not allowable expenses. Where a cost has both business and personal use, only the business element can be claimed.

Possible categories include:

This does not mean that every cost within those categories is automatically deductible. The purpose of the expenditure, accounting method, supporting evidence and any personal element must be considered.

If you use the £1,000 trading allowance, you cannot also deduct actual business expenses against the same income in the usual way.

Professional fees incurred for business purposes can qualify as business expenses. However, the personal cost of preparing and submitting the Self Assessment tax return itself is not listed as an allowable business expense in the relevant GOV.UK guidance.

Where an accountant's invoice covers both business accounts and personal tax-return work, the nature of each part should be identified rather than treating the complete fee as automatically allowable.

From the 2024/25 tax year, cash basis is the default accounting method for most eligible self-employed businesses unless the business opts out or cannot use it. Under cash basis, income and expenses are generally recorded when payment is received or made. Traditional accounting generally records income when invoiced and expenses when billed.

The accounting method can affect which tax year includes a transaction. Do not switch methods or move income between periods simply to produce a preferred tax result.

If your records do not follow the tax year, additional work may be needed to allocate profits correctly.

Some taxpayers must make payments on account towards a future Self Assessment liability. There can be a payment deadline on 31 July as well as the January deadline.

This can surprise a first-time filer because the amount requested may include:

• • The balancing amount for the completed tax year
• • A first payment on account towards the following year

Whether payments on account apply, and their amount, depends on the taxpayer's actual calculation. Avoid presenting them as a penalty or an additional tax charge.

Filing early provides more time to understand what is due and plan for the payment dates.

From 6 April 2026, Making Tax Digital for Income Tax applies to a sole trader or landlord who is registered for Self Assessment, receives qualifying self-employment or property income, is not exempt and had qualifying income above £50,000 for 2024/25. Further published thresholds are above £30,000 for 2025/26, leading to entry from 6 April 2027, and above £20,000 for 2026/27, leading to entry from 6 April 2028.

Qualifying income generally combines gross income before expenses from self-employment and property. Taxpayers remain responsible for checking their position even if they do not receive a letter from HM Revenue & Customs. The treatment of joint property, residence, ceased income sources and unusual arrangements may require a separate review.

Read our MTD guide or review the official Making Tax Digital collection.