--- title: "Self Assessment Tax Returns in Cardiff | Luminaire Accounts" description: "Get your HMRC Self Assessment filed on time, with expenses and reliefs checked. Clear tax summary plus payment dates and next steps." canonical: "https://hlsaccounting.co.uk/services/self-assessment-tax-returns" --- Tax Services - Personal # Self Assessment Tax Returns We help sole traders, freelancers and small business owners across Cardiff and South Wales file accurate self-assessment tax returns on time, without the stress. With nearly ten years of experience and a friendly, no-jargon approach, we'll handle your return from start to finish so you can focus on running your business. [Book a free consultation](https://calendly.com/hlsaccounting/new-client-meeting) 10 Years experience 300+ Returns filed 100% On-time submissions ![Adult seated at a desk in a tidy home office reviewing financial documents and using a laptop, pen, and calculator in a focused, organized scene.](/_next/image?url=%2Fapi%2Fmedia%2Ffile%2Ftax_return_home_office_realistic_studio_photo.png%3Fv%3D1773064205253&w=1536&q=75&dpl=dpl_DEc4fGhEc1SCRZZutzoEsRuDy1CJ) ## Everything under Self Assessment Whether you're a sole trader with simple accounts or juggling multiple income streams, we cover all aspects of self-assessment tax returns and make sure nothing gets missed. ### Sole Trader Returns Complete tax returns for self-employed individuals, including income and expense records, allowable deductions, and Class 2 and Class 4 National Insurance calculations. ### Multiple Income Sources Returns for individuals with employment income, rental property, dividends, interest, pensions, or benefits in kind — all consolidated into one accurate submission. ### Partnership Returns Self-assessment filings for business partners, including your share of partnership profits and any additional personal income. ### HMRC Enquiry Support Full representation and correspondence handling if HMRC selects your return for review or requests further documentation. ## How we handle your self-assessment return If you're self-employed, a freelancer, or earn income from more than one source, HMRC requires you to file a self-assessment tax return each year. The deadline is strict: January 31st following the end of the tax year. We take care of the entire process for you, from collecting your paperwork to submitting the return and liaising with HMRC on your behalf. Our approach is straightforward. You send us your records — invoices, receipts, bank statements, P60s, dividend vouchers, whatever applies to your situation. We prepare your accounts, calculate your tax liability, identify any reliefs or allowances you're entitled to, and file everything online before the deadline. You'll know exactly what you owe, when it's due, and how we arrived at the figures. > We've never missed a deadline, and we check every return twice before it goes to HMRC. More information ### What's included - Collection and review of all relevant financial documents - Preparation of income and expenditure accounts for sole traders - Completion and submission of your SA100 tax return - Calculation of Income Tax, Class 2 and Class 4 National Insurance - Identification of applicable tax reliefs and allowable expenses - Advice on minimising your tax liability within the rules - All correspondence with HMRC as your appointed agent Many of our clients are Cardiff-based tradespeople, salon owners, dental and aesthetic practitioners, or small business owners who've outgrown DIY software or just want the peace of mind that comes with professional support. If you've been selected for an HMRC enquiry, we represent you throughout and handle all the back-and-forth. Self-assessment covers worldwide income, so if you have overseas earnings, rental income abroad, or foreign dividends, we make sure everything is disclosed correctly. We also keep you informed about payment dates — your January payment on account, your July balancing payment — so there are no surprises. If your circumstances change mid-year, we can advise on whether adjustments are needed. **Common concerns we address:** - **Late filing penalties:** We work to agreed timelines and always build in a buffer before the January 31st deadline. - **Incorrect figures:** Every return is checked against your source documents and reviewed by a qualified accountant before submission. - **Missing records:** We'll help you reconstruct what you need and advise on record-keeping going forward. - **Overpaying tax:** We actively look for reliefs, allowances and deductions that apply to your situation. We serve clients across South Wales, including Pontypridd, Newport, Barry, Penarth, and the Vale of Glamorgan. Most of our work is done remotely, but we're always available for a call or a face-to-face meeting at our Cardiff office if you prefer to talk things through in person. Once your return is filed, you'll receive a copy for your records along with a clear summary of your tax position and any payments due. ### Ready to talk? Book a free consultation and we'll explain exactly how we can help with your self-assessment return. [Book a free consultation](https://calendly.com/hlsaccounting/new-client-meeting) ### You might also like - [Dividend Tax Planning](/services/dividend-tax-planning)→ - [Rental Income Tax Returns](/services/rental-income-tax-returns)→ - [High Income Child Benefit Charge Returns](/services/high-income-child-benefit-charge-returns)→ ## Worth considering Tax Services - Personal ### Tax Rebates & Refund Claims We identify overpaid tax and submit accurate HMRC rebate and refund claims for sole traders and small businesses, then chase progress until payment lands. [Tax Rebates & Refund Claims→](/services/tax-rebates-and-refund-claims) Tax Services - Personal ### HMRC Investigation Support Support for HMRC enquiries and investigations, from the first letter to closure. We review your records, manage HMRC correspondence and help resolve tax and penalties. [HMRC Investigation Support→](/services/hmrc-investigation-support) Tax Services - Personal ### Non-Resident Tax Returns Preparation and filing of UK non-resident Self Assessment returns, including UK property income, relief claims and HMRC follow-up, so you stay compliant. [Non-Resident Tax Returns→](/services/non-resident-tax-returns) Tax Services - Personal ### Inheritance Tax Planning Inheritance tax planning that maps your estate, estimates IHT, and sets a clear action plan using reliefs, gifting and ownership changes where suitable for you. [Inheritance Tax Planning→](/services/inheritance-tax-planning) Tax Services - Personal ### Capital Gains Tax Advice Practical Capital Gains Tax advice for business owners and sole traders. We calculate gains, check reliefs and handle HMRC reporting and deadlines across South Wales. [Capital Gains Tax Advice→](/services/capital-gains-tax-advice) Tax Services - Personal ### Personal Tax Planning Personal tax planning for Cardiff business owners and sole traders. Forecast your tax bill, use key allowances, and plan payments and profit withdrawals. [Personal Tax Planning→](/services/personal-tax-planning) ## Before you book Here are the questions we hear most often from clients about self-assessment tax returns. When do I need to file a self-assessment tax return? You must file if you're self-employed and earned more than £1,000, a partner in a business partnership, have untaxed income over £2,500 (e.g. rental income, dividends), or HMRC has sent you a notice to file. The deadline for online filing is January 31st following the tax year end. What documents do I need to provide? Typically your business income records (invoices, sales), expense receipts, bank statements, P60 or P45 if you're also employed, dividend vouchers, pension statements, and details of any other income like rental or savings interest. We'll give you a tailored checklist when you book. How much does it cost? Our self-assessment service starts from £150 for straightforward sole trader returns. The exact fee depends on the complexity of your income sources and the volume of transactions. We'll give you a fixed quote after an initial conversation, with no hidden charges. Can you help if I've missed the deadline? Yes. We can still prepare and file your return, though HMRC will apply late filing penalties (£100 after January 31st, increasing over time). We'll submit as quickly as possible to minimise further penalties and liaise with HMRC on your behalf. What if HMRC queries my return? As your appointed agent, we handle all HMRC correspondence. If your return is selected for enquiry, we'll represent you throughout, provide the documentation they request, and negotiate on your behalf. This service is included in our ongoing support. Do you work with clients outside Cardiff? Absolutely. While we're based in Cardiff, we work with sole traders and small businesses across South Wales — including Newport, Pontypridd, Barry, Penarth, and the Vale. Most of our work is done remotely, with secure document sharing and video calls as needed. How do you identify tax savings? We review your expenses to ensure all allowable costs are claimed, check eligibility for reliefs like capital allowances or pension contributions, and advise on timing strategies for income and payments. We stay up to date with HMRC rules so you don't miss out. Will I need to keep records after you file my return? Yes. HMRC requires you to retain supporting records for at least five years after the January 31st filing deadline. We'll advise you on what to keep and how to organise it, and we can store digital copies securely if that helps. ## Let's talk about your self-assessment return Book a free consultation and we'll walk you through the process, answer your questions, and give you a fixed-price quote with no obligation. [Book a free consultation](https://calendly.com/hlsaccounting/new-client-meeting)