If you need to complete a Self Assessment tax return for the 2025/26 tax year, 31 January 2027 is the date to keep firmly in mind. Your online return must normally be submitted by then, and any tax due must also be paid by the same deadline.
For anyone looking for a tax accountant in Barnet, the best time to get organised is well before January arrives. Leaving everything until the final few weeks gives you less time to find missing records, check expenses, understand the tax bill and deal with any unexpected issues.
We work with individuals, freelancers, landlords, directors and business owners across Barnet and North London who want their Self Assessment dealt with properly without turning January into a last-minute scramble.
Why the 31 January deadline matters
The 31 January deadline covers two important things: submitting your online Self Assessment return and paying the tax you owe.
For the 2025/26 tax year, which ran from 6 April 2025 to 5 April 2026, the online filing and payment deadline is 31 January 2027. You can check the current Self Assessment deadlines if you are unsure which date applies to you.
There is no advantage in waiting until January simply because the deadline falls then. Filing earlier gives you a clearer idea of what you owe and more time to prepare for the payment.
If you have been looking for a tax accountant in Barnet because your records are still unfinished, October, November and December are all far better times to sort them out than the last week of January.
Who might need to complete a Self Assessment?
Self Assessment is not limited to people who consider themselves self-employed.
You may need to complete a return if you have income that has not already been taxed appropriately through PAYE or another system. Common situations include:
- self-employment or freelance income
- rental income
- partnership income
- certain investment or savings income
- Capital Gains Tax matters
- overseas income
- more complicated combinations of employment and other income
Directors and business owners can also find themselves dealing with personal tax matters alongside their company accounts.
The circumstances vary considerably, which is where speaking to a tax accountant in Barnet can help. We can look at the full picture rather than assuming that one source of income tells the whole story.
Our Self Assessment service covers everything from calculating the liability and preparing the return to advising on payment dates and appropriate record retention.
Missed the 5 October registration deadline?
People completing Self Assessment for the first time normally need to register before they can file their return.
For the 2025/26 tax year, the normal registration deadline was 5 October 2026. If you should have registered but have missed that date, do not wait until January to deal with it.
Late registration does not make the tax obligation disappear. If you register after 5 October, you may be given a different filing deadline, but tax owed for 2025/26 is still normally due by 31 January 2027.
The practical response is simply to get the process moving as soon as possible. You will need your tax reference details before the return can be completed properly, so delaying registration can create a bottleneck later.
If you are unsure whether you should have registered at all, we can also help you establish whether Self Assessment applies before you start gathering unnecessary paperwork.
What should you give your accountant?
A tax return is much easier to prepare when the records arrive in reasonable order.
The exact information will depend on your circumstances, but we may need things such as:
- P60s and P45s
- details of freelance or self-employed income
- invoices and business expense records
- rental income and property expenses
- savings and investment statements
- pension contribution information
- dividend records
- details of asset sales
- overseas income information
- previous tax returns or correspondence where relevant
You do not need to understand where every figure belongs on the return before sending it to us. That is our job.
What helps is giving us complete information and mentioning anything unusual rather than assuming it does not matter. A missing property statement, forgotten investment disposal or additional freelance income can change the final position.
If your search for a tax accountant in Barnet has started because your records are scattered across emails, spreadsheets and bank accounts, do not let that stop you from making contact. We can tell you what is actually needed and help you work through it systematically.
Do not overlook allowable expenses
For self-employed people, landlords and other individuals with business-related income, allowable expenses can have a meaningful effect on taxable profit.
The key is claiming expenses that genuinely relate to the business rather than trying to turn personal spending into business expenditure.
Depending on the type of work you do, allowable costs might include:
- professional subscriptions
- accountancy fees
- business insurance
- certain travel costs
- software and subscriptions
- marketing
- office expenses
- equipment
- qualifying home-working costs
Different rules apply to different types of income, so a landlord’s expenses will not necessarily be treated in the same way as a freelancer’s.
A good tax accountant in Barnet should look beyond simply entering the figures supplied. We want to understand what the expenditure relates to so legitimate deductions are not missed and inappropriate claims are not included.
Why filing earlier can help with cash flow
One of the biggest benefits of completing Self Assessment early is knowing the tax bill before it becomes urgent.
Submitting your return in October does not normally mean you suddenly have to pay in October. The standard payment deadline remains 31 January. It simply means you have more time to prepare.
For example, if your return shows a larger bill than expected, knowing that in November gives you far more room to organise your finances than discovering it on 29 January.
This can be particularly important for freelancers and business owners whose income changes from year to year.
We regularly encourage clients to think about tax as part of normal cash-flow planning rather than treating it as a surprise annual expense. Our personal tax planning services look beyond the return itself and consider the wider tax position throughout the year.
Watch out for payments on account
The amount due on 31 January may not consist solely of the tax relating to the year you have just reported.
Some Self Assessment taxpayers also need to make payments on account towards the following year’s bill. These are advance payments, usually made in two installments, with the first falling on 31 January and the second on 31 July.
That can make the January payment noticeably larger than someone filing for the first time expected.
If your income has fallen substantially, there may be circumstances where payments on account can be reduced. They should not simply be lowered because the January bill feels uncomfortable, though. If they are reduced too far and your eventual liability is higher, additional amounts and interest may become due.
A tax accountant in Barnet should explain what makes up the January figure rather than simply giving you one number to pay.
You should know which part relates to the previous tax year, which part is an advance payment and what may still be due later.
Self Assessment is about accuracy, not simply meeting the deadline
Submitting a return on 30 January may technically be on time, but filing on time is only one part of getting Self Assessment right.
The figures also need to be complete and accurate.
Common problems can include:
- leaving out a source of income
- claiming personal spending as a business expense
- forgetting property income
- missing investment or savings information
- recording income in the wrong tax year
- failing to include relevant overseas income
- misunderstanding payments on account
Mistakes do not always mean someone has deliberately done anything wrong. Tax affairs become complicated very quickly when there are several sources of income.
Working with an accountant gives you another set of eyes on the information before the return is submitted.
Local support can still make a difference
Tax returns can be completed digitally, so technically your accountant could be based almost anywhere.
There are still advantages to working with someone local.
If you are searching for a tax accountant in Barnet, you may want the option of meeting someone in person rather than dealing entirely through a portal or call centre. You may also prefer a firm that already works with individuals and businesses across Barnet, Finchley, Whetstone and the surrounding parts of North London.
We are based in Whetstone and work with clients both face to face and remotely. That gives you the flexibility to send records electronically while still having local support available when a conversation is easier in person.
For many clients, the relationship also continues beyond one tax return. Once we understand your income, business and longer-term plans, future tax planning becomes much more useful.
Do not wait until January to ask questions
The closer 31 January gets, the less room there is to solve problems.
You might discover that:
- an important statement is missing
- you have not registered correctly
- rental records are incomplete
- you cannot identify some transactions
- your previous return contains an error
- you have income you are unsure how to report
- the tax bill is larger than expected
None of these automatically means disaster. They are simply much easier to deal with when there is time.
If you have already been searching for a tax accountant in Barnet, that is usually a good sign that there is something you would rather have checked before filing. Getting advice now gives you time to gather the right information and understand the outcome properly.
Self Assessment can also highlight wider tax planning opportunities
A tax return looks backwards because it reports income and gains from a tax year that has already ended.
Good tax advice should also look forwards.
Once your return has been prepared, it may become clear that there are areas worth reviewing before the current tax year ends on 5 April. That could involve pension contributions, business structure, expected investment disposals, property income or the way you are setting money aside for future liabilities.
Not every client needs complicated tax planning. Sometimes the most useful change is simply improving record-keeping or putting aside tax monthly rather than trying to find the entire amount in January.
Our approach is to look at your actual circumstances rather than applying the same checklist to everyone.
Choosing a Tax Accountant in Barnet Before 31 January
If you are comparing services for a tax accountant in Barnet, look for more than someone who can type figures into a return.
You want someone who will check the information, explain the tax calculation clearly and tell you what needs attention before the next deadline arrives.
It is worth asking:
- Does the firm regularly prepare Self Assessment returns?
- Can they help if your records are incomplete?
- Do they offer personal tax planning as well as filing?
- Can they deal with property, freelance or investment income?
- Will they explain the amount due and when it needs to be paid?
- Can you speak to someone when your circumstances change?
The goal should be to come away understanding your tax position rather than simply receiving a completed form.
Get your Self Assessment organised before 31 January
The deadline for the 2025/26 online Self Assessment return is 31 January 2027, but there is little benefit in treating that as the date to start dealing with it. Starting earlier gives you time to gather records, check the numbers, understand the bill and resolve questions without January pressure.
If you are looking for a tax accountant in Barnet for Self Assessment support, we can help. Our team provides Self Assessment support alongside broader personal tax planning throughout the year.
You can contact us to discuss your 2025/26 return and get the process moving well before 31 January.
