Your Questions Answered

Self Assessment (or SA100) is how you tell HMRC about any income they don’t already have the full picture on – things like self-employed work, rent, or certain investments. You send HMRC a tax return so they can check whether you’ve paid the right amount of tax for the year.

You may need to file if, for example, you’re self-employed, a landlord, a company director receiving dividends, have untaxed or foreign income, earn over £150,000 pa, or are affected by the High Income Child Benefit Charge.

Also, you may have received a letter from HMRC asking you to complete a return.

If you’re unsure, don’t worry – we’ve created a simple guide that explains who usually needs to file and why.

For a typical tax year:

• 31 October – deadline for paper tax returns
• 30 December - deadline if you want any tax due to be collected through your PAYE tax code
• 31 January – deadline for online tax returns and paying most tax bills

If you miss the online filing deadline (31 January), HMRC charges an automatic £100 late filing penalty, even if you don’t owe any tax.

Further delays can lead to extra penalties and interest. If you’re already late, we can still help you get back on track as quickly as possible.

Tax Online is here to take the stress out of Self Assessment. Instead of wrestling with HMRC forms, you:

• Answer straightforward questions in plain English
• Add your income and expense details in a guided way
• Let us turn that into a properly prepared tax return ready to be filed with HMRC

We handle the structure, calculations and “tax speak” behind the scenes, so you can focus on answering clear, simple questions.

No. Tax Online is built for people who don’t like dealing with numbers or forms. We:

• Break things into small steps
• Explain any jargon in clear English
• Do the calculations for you in the background

If something doesn’t make sense, you’re encouraged to ask rather than guess.

Tax Online is designed for everyday people with common tax situations, including:

• Self-employed people and freelancers – including side hustles and gig-economy work
• People renting out property or a spare room – whether it’s a single buy-to-let, a room in your home, or an Airbnb
• Company directors receiving dividends
• Individuals with income from savings, investments, shares or crypto
• People with income from overseas, such as foreign property, pensions or work
• Families affected by the High Income Child Benefit Charge
• Anyone catching up on late or previous-year tax returns

If you’re lucky enough to have more than one buy-to-let property, we’ll refer you to our specialist tax consultants, who look after clients with larger property portfolios and can provide more tailored support. This is a separate, more bespoke service, and we’ll always explain the options and fees clearly before you decide what to do.

Take our fun quiz to see if you need to submit a self assessment tax return - click here

You don’t need to know everything off the top of your head. It helps to have:

• Your National Insurance number
• Your Unique Taxpayer Reference (UTR), if you already have one
• P60, P45 or P11D from any jobs you’ve had
• Details of self-employed income and expenses
• Rental income and costs (e.g. letting fees, repairs, insurance, allowable mortgage interest)
• Statements showing interest from savings and dividends
• Details of anything you’ve sold that might be liable to Capital Gains Tax (shares, second homes, certain crypto)

Tax Online will guide you section by section so you can gather what you need without panic.

Yes – first-time filers are a big part of who we help. We will:

• Explain how to register for Self Assessment if you haven’t already
• Help you understand what HMRC is asking for
• Guide you through your first return in simple, easy to understand steps

Our aim is to take the stress off and make it all feel manageable. So no need to put it off.

In most cases, yes. If you’ve missed deadlines, received penalty letters, or just haven’t got round to filing in past years, we can help you:

• Work out what information is needed
• Prepare and submit outstanding returns
• Understand what penalties or interest may apply

Getting things up to date usually feels a lot better than waiting and worrying.

If HMRC has asked you to complete a tax return, you’re normally required to do so, even if you think you don’t meet the usual criteria.

Tax Online can help you understand what they’re asking for, gather the right information, and get the return filed correctly.

Once your return is submitted and processed, you’ll see how much tax is due and by what date. You can usually pay HMRC by:

• Bank transfer
• Online banking
• Debit/credit card
• Setting up a payment plan (in some cases)

If you’re worried about paying in full, HMRC may allow a Time to Pay arrangement, where you spread the cost over monthly instalments.

Don’t worry we will provide all the payment details at the appropriate time.

Yes. Protecting your information is a top priority for Tax Online. We use secure, encrypted systems for all client data, and we follow strict GDPR and UK data-protection rules. Only authorised team members can access your information, and we regularly train our staff to maintain the highest standards of confidentiality.

We also use secure methods for sending and receiving documents, ensuring your financial information is safe at every step.

Your information is not shared with other companies for marketing, and you stay in control of your account.

Tax Online is designed to help you accurately complete and file your tax return and to highlight common allowances and reliefs.

If your situation is particularly complex (for example very high income, large capital gains, multiple companies or a big property portfolio), we may recommend speaking to a specialist tax adviser. Where appropriate, we can introduce you to our tax consultants for more tailored, one-to-one advice.

Our pricing is clear and transparent, £149 with no hidden charges. 

Once we have all of your information, most tax returns are completed within 5-10 working days. We'll always aim to get your draft tax return over to you as soon as possible. 

If HMRC contact you after your tax return is filed, you may need to get advice from an Accountancy firm who can help guide you through. Sometimes these situations can be complex and go on for months so it's best to engage with somebody who can assist you throughout this time. 

Tax Online only deals with submitting your tax return from the information you provided in the format that HMRC requires and with us making sure everything is stacked correct. If we identify something that clearly looks wong we'll flag this with you before any submissions.

Yes. You will always have the chance to review and approve your tax return before anything is submitted to HMRC. Nothing is filed without your confirmation.

If you notice you've made a mistake after you've completed answering all the questions in your dashboard or when we send you the draft tax return to approve, just let us know and we'll make the change. You'll have direct access to our team through our support desk from your client area

Yes. We use secure, HMRC-recognised filing software. Your return is submitted electronically through approved channels, and you’ll receive official confirmation once HMRC has processed it.

Yes, we can help many clients who live abroad but need to file a UK tax return. If your circumstances require specialist cross-border tax advice, we can introduce you to our tax consultants for more tailored, one-to-one advice.