Oxford's results-driven accountancy & business advisory practice. 01865 764 321 info@conwaypartners.co.uk

Self Assessment

Accurate, on-time tax returns — whether it’s your first or your fifteenth.

Overview

Self Assessment

Whether it’s your first time filing or you’ve been doing it for years, we make sure your Self Assessment is completed accurately and on time, every time — with no last-minute panic and no nasty surprises from HMRC.

We take the time to understand your full picture — employment, self-employment, rental income, dividends, capital gains or a mix of everything — so nothing is missed and every allowance and expense you’re entitled to is claimed.

More than just filling in a form, we use your return as a chance to look ahead: flagging ways to be more tax-efficient next year, making sure your payments on account are right, and giving you clear, jargon-free answers whenever HMRC comes calling. You hand over the paperwork; we handle the rest.

Self Assessment

Personal tax returns

SA100 returns prepared, checked and filed on time.

Sole trader & self-employed

Accounts and returns for the self-employed, done properly.

Landlords & rental income

Property income reported correctly, reliefs claimed in full.

Capital gains reporting

Disposals reported accurately, with reliefs applied.

Payments on account

We check your payments are right — never over, never under.

HMRC support

We deal with HMRC on your behalf, so you don’t have to.

Our Approach

How We Work With You

A straightforward process built around you and your business.

01

Listen

We start by getting to know you, your business and what you actually need from us.

02

Plan

We put together a clear plan that’s right for your situation, whether you’re just starting out or looking to grow.

03

Deliver

We get everything done properly and on time, keeping you informed every step of the way.

04

Support

We don’t just disappear after the work is done. We keep reviewing and checking in so you always have the right support as your business changes.

Common Questions

Frequently Asked Questions

Straight answers to the questions we’re asked most often.

Do I need to file a Self Assessment tax return?

You’ll usually need to file if you’re self-employed earning over £1,000, a landlord with rental income, liable for the High Income Child Benefit Charge, or receiving untaxed income such as dividends, capital gains or foreign income. If you’re not sure, ask us — it takes minutes to confirm either way.

When is the Self Assessment deadline?

Online returns and any tax owed are due by 31 January following the end of the tax year; paper returns are due earlier, by 31 October. If it’s your first return, you need to register with HMRC by 5 October after the tax year ends. We prepare and file well ahead of the deadline, so January is never a panic.

What happens if I file my tax return late?

HMRC charges an automatic £100 penalty the moment the deadline passes, even if you owe no tax. After three months, daily penalties of £10 can run up to £900, with further penalties at six and twelve months, plus interest on any unpaid tax. It’s entirely avoidable — which is exactly why our clients file early.

What expenses can I claim if I’m self-employed?

You can claim costs incurred wholly and exclusively for your business — equipment, business travel, use of home, insurance, professional fees and relevant subscriptions among them. What counts varies by trade, and missed claims are money left on the table, so we go through your situation carefully to make sure everything you’re entitled to is claimed.

What are payments on account?

They’re advance payments towards next year’s tax bill, due on 31 January and 31 July, each usually half of your previous year’s liability. If your income has dropped, they can often be reduced so you’re not overpaying up front. We check yours every year as part of preparing your return.

Explore More

Our Services

Everything you need, all in one place.

Ready to talk it through?

Book a free, no-obligation consultation and we’ll show you exactly how we can help.

Free initial consultation · Oxford-based, UK-wide · Fixed-fee clarity
Scroll to Top