--- title: "Self Assessment Tax Returns in Cardiff | TCK Accounting" description: "Accurate Self Assessment preparation and HMRC filing for sole traders and directors. Capture all income and expenses and meet deadlines." canonical: "https://www.tckaccounting.co.uk/services/self-assessment-tax-return-preparation-and-filing" --- ![A UK small business owner sits at a desk with a laptop and papers in an office setting, depicted in a neutral editorial illustration.](/_next/image?url=%2Fapi%2Fmedia%2Ffile%2Fmtd-income-tax-qa-hero.png%3Fv%3D1769183236465&w=1536&q=75&dpl=dpl_HkjxAMLz8SoKDEaYz6gDcGJLMf1v) Self Assessment tax returns # Self Assessment Tax Return Preparation & Filing [Book a free consultation](https://www.tckaccounting.co.uk/redirect-contact) Self Assessment tax return preparation and filing gives you confidence that your income, expenses, and claims are reported correctly to HMRC. We pull your figures together, check what can be claimed, calculate your tax position, and submit your return on time, with clear explanations of what you owe and when. ## What this service covers Self Assessment can be straightforward or messy, especially when you have multiple income streams. This service is built to make it accurate, compliant, and easy to sign off. - Collection and review of your income sources (for example self-employment, director dividends, property income, interest, or capital gains) - Review of allowable expenses and business use adjustments - Checks for common reliefs and allowances (where applicable), such as pension contributions and Gift Aid - Capital gains and property reporting support where relevant - Tax calculation, Payments on Account review, and what to budget for - Preparation and submission of your Self Assessment return to HMRC - Plain English summary of what was filed and the key dates ahead ### Who this is for This service suits people who want their return handled properly without spending evenings second guessing rules and receipts. It is a good fit if you are a sole trader, freelancer, contractor, or company director who also has other income to report. It is also useful if this is your first return, your income has changed, or you want to be confident you are claiming what you are entitled to. ### How it works We start by confirming which returns and schedules are needed, then provide a clear list of what to share and in what format. You send your records, we review and ask focused questions where something is unclear, then we draft the return and share the figures for approval. Once you confirm, we file with HMRC and provide a summary of the outcome and deadlines. ### After filing You will receive a breakdown of your tax due, the payment deadlines, and any expected Payments on Account so you can plan cash flow. If anything looks unusual compared with previous years, we will flag it and explain why. If you want ongoing support, we can also help you set up a smoother record keeping process for next year’s return. [Book a free consultation](https://www.tckaccounting.co.uk/redirect-contact) ## Frequently Asked Questions What information do you need to prepare my Self Assessment return? Typically we will ask for your income details (self-employment, dividends, employment, rental, interest) and a summary of your expenses with supporting records. If you have used accounting software, we can usually work from your reports plus a few confirmations. Can you handle a return with multiple income sources? Yes. We can include employment, self-employment, dividends, property income, savings income, and capital gains where relevant. We will confirm what applies to you and make sure the right sections are completed. When should I get started for the 31 January deadline? As early as you can, especially if your records need tidying or you have more than one income source. Starting early gives time to answer queries and plan for the payment rather than rushing at the deadline. Will you tell me what expenses and allowances I can claim? Yes. We review your expense categories and ask questions to make sure claims are both accurate and supportable. We will also check common reliefs and allowances that may apply to your circumstances. What if I have already filed, received a penalty, or got a letter from HMRC? We can review what has happened and advise on the next steps, such as correcting errors, responding to HMRC, or preparing the next return more cleanly. If there is a penalty or notice, we will explain what it relates to and what information is needed to deal with it. [Book a free consultation](https://www.tckaccounting.co.uk/redirect-contact) ## Related Services Complete your experience with these services - Self Assessment Income, Gains & Expenses Review [View](/services/self-assessment-income-gains-and-expenses-review) - Self Assessment Penalty Avoidance Support [View](/services/self-assessment-penalty-avoidance-support) - Early Self Assessment Filing (Plan Your Tax Bill) [View](/services/early-self-assessment-filing-plan-your-tax-bill) - Paper Self Assessment Return Support (31 October) [View](/services/paper-self-assessment-return-support-31-october) Show more services - Self Assessment Deadline Management (31 January) [View](/services/self-assessment-deadline-management-31-january) - Self Assessment After an HMRC Notice to File [View](/services/self-assessment-after-an-hmrc-notice-to-file) - Self Assessment for Additional Income Sources [View](/services/self-assessment-for-additional-income-sources) - Self Assessment for Child Benefit High Income Charge [View](/services/self-assessment-for-child-benefit-high-income-charge) - Self Assessment for High Earners (Over £100k) [View](/services/self-assessment-for-high-earners-over-pound100k) - Self Assessment for Landlords (Rental Income) [View](/services/self-assessment-for-landlords-rental-income) - Self Assessment for Self-Employed Individuals [View](/services/self-assessment-for-self-employed-individuals) - Self Assessment for Company Directors [View](/services/self-assessment-for-company-directors) ## Related Blog Posts - [![A clean illustration of a UK office desk setup with documents and a PAYE notice.](/_next/image?url=%2Fapi%2Fmedia%2Ffile%2Fhmrc-self-assessment-through-paye-hero.png%3Fv%3D1769514411339&w=1536&q=75&dpl=dpl_HkjxAMLz8SoKDEaYz6gDcGJLMf1v) ### Can I Pay My Self Assessment Bill Through My PAYE Tax Code? Yes—HMRC may collect Self Assessment through your PAYE tax code if you meet the rules, including the £3,000 limit and deadlines. Read more ](/blog/can-i-pay-my-self-assessment-bill-through-my-paye-tax-code) - [![Illustration of a desk with financial documents and a calculator in a typical UK small business setting.](/_next/image?url=%2Fapi%2Fmedia%2Ffile%2Fpayments_on_account_uk_hero.png%3Fv%3D1769514406259&w=1536&q=75&dpl=dpl_HkjxAMLz8SoKDEaYz6gDcGJLMf1v) ### Payments on Account: How They’re Calculated, Who Pays, and the Due Dates Payments on account explained: how HMRC calculates them, who pays, due dates (31 Jan & 31 Jul), and when you may not have to pay. Read more ](/blog/payments-on-account-how-theyre-calculated-who-pays-and-the-due-dates) Show more posts - [![A person at a desk reviewing documents and using a computer in a calm home office environment.](/_next/image?url=%2Fapi%2Fmedia%2Ffile%2Fcorrecting-return-after-filing-hero.png%3Fv%3D1769514404538&w=1536&q=75&dpl=dpl_HkjxAMLz8SoKDEaYz6gDcGJLMf1v) ### How to Correct a Self Assessment Tax Return After Submission How to amend a UK Self Assessment tax return after filing, including the 72-hour online wait and the 12-month correction window. Read more ](/blog/how-to-correct-a-self-assessment-tax-return-after-submission) - [![Person at a desk in a small office environment reviewing documents and using a laptop, symbolizing business accounts preparation.](/_next/image?url=%2Fapi%2Fmedia%2Ffile%2Fqa-filing-profit-figures-uk-business.png%3Fv%3D1769514403751&w=1536&q=75&dpl=dpl_HkjxAMLz8SoKDEaYz6gDcGJLMf1v) ### Do I Still File a Self Assessment Return if I Don’t Know My Profit Yet? Yes—HMRC says you must still file. Use provisional figures, tell HMRC, then amend your return once your final profit is known. Read more ](/blog/do-i-still-file-a-self-assessment-return-if-i-dont-know-my-profit-yet) - [![A computer on a desk in a small business office setting, displaying accounting software.](/_next/image?url=%2Fapi%2Fmedia%2Ffile%2Fhmrc-vat-software-editorial-uk-small-business.png%3Fv%3D1769183233536&w=1536&q=75&dpl=dpl_HkjxAMLz8SoKDEaYz6gDcGJLMf1v) ### MTD for VAT Penalties: What HMRC Says About Filing Without Functional Compatible Software HMRC says it may charge a penalty of up to £400 for every VAT return filed without functional compatible software under MTD for VAT. Read more ](/blog/mtd-for-vat-penalties-what-hmrc-says-about-filing-without-functional-compatible-software)