3 things to check before filing your self assessment tax return

Nov 14, 2025
2 min read

Before filing your UK Self Assessment tax return, there are a few key things to double-check to ensure everything is correct and that you avoid any issues down the line. Here are three important things to check:

1. Income and Earnings

Have all your income sources been included? This includes:
- Employment income (P60, P11D if applicable).
- Self-employment or business income (income and expenses).
- Rental income (details of rental property income, expenses, and allowable deductions).
- Dividend income and interest from savings or investments.
- Foreign income or overseas earnings (if applicable).
- Any other income sources like pensions, benefits, etc.

2. Allowable Expenses and Deductions

Have you claimed all eligible expenses for your self-employment or business activities? This might include:
- Office supplies, software, and equipment.
- Travel costs, including car mileage if applicable.
- Home office costs (if working from home), like a portion of rent, utilities, and internet.
- Professional fees or memberships.
- Any other costs directly related to earning your income.

3. Tax Reliefs and Allowances

Have you claimed all available tax reliefs and allowances? Some common ones are:
- Marriage Allowance or Blind Person’s Allowance (if applicable).
- Pension contributions (if contributing to a private pension).
- Gift Aid donations (ensure you have evidence of donations).
Are you claiming the correct tax-free personal allowance?

How does LHP help on these 3 things?

Are there any discrepancies between the records you have and the tax return? Check for missing income or unreported amounts from HMRC records.
Ensure you’ve checked the latest rules for allowable expenses to avoid claiming anything that might not be permitted or has changed recently.
Checking all allowances are considered and claimed where appropriate

Using LHP Accountants Limited to prepare your self assessment tax returns will support you through the process and help avoid errors, penalties, or missing out on any tax-saving opportunities.

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