You have just gone freelance. Congratulations. You have made one of the best decisions of your working life. It also comes with a financial learning curve nobody properly prepares you for.

Your employer used to handle tax, National Insurance, pensions, and payroll. Now that is all on you. The good news: it is entirely manageable. The bad news: most freelancers learn the hard way, usually around January when HMRC sends them a bill they were not expecting.

This guide covers the money side of your first year. No jargon, no fluff. Just the things you actually need to do, roughly in the order you need to do them.

1. Register with HMRC for Self Assessment

This is step one, and you should not put it off. As a self-employed person in the UK, you need to register for Self Assessment with HMRC. When you register, you will receive a Unique Taxpayer Reference (UTR), a 10-digit number that stays with you for life. You will need it to file your tax return and to deal with HMRC on anything tax-related.

The official deadline to register is 5 October after the end of your first tax year. So if you start freelancing any time between 6 April 2025 and 5 April 2026, you must register by 5 October 2026.

But here is the practical advice: do not wait until October. The registration process takes time. HMRC sends your UTR by post, not email, and it typically takes 10 to 15 working days to arrive. Then you need to activate your online account within 28 days. During busy periods, delays are common. Register as soon as you start freelancing. Get it out of the way.

If you miss the deadline and you owe tax, HMRC can charge failure-to-notify penalties. Not worth the risk.

2. Open a separate bank account

This is not a legal requirement, but it is one of the most practical things you can do for yourself. Open a bank account that you use only for business. All client payments go in. All business expenses come out.

Why? Because when everything sits in one account, you lose visibility. That balance you see is not really your money. Part of it belongs to HMRC, and another part is already committed to expenses you have not paid yet. Mixing personal and business money is how freelancers end up spending their tax reserves on a holiday in August and panicking in January.

A separate account gives you a clean picture. You can see exactly what came in, what went out, and what is left. It also makes your bookkeeping dramatically easier when tax return season arrives. Most business current accounts for sole traders are free or very cheap.

3. Set aside tax from day one

This is the single most important habit you can build. Every time money comes in from a client, move a percentage into a separate savings pot or account. Do not touch it. That money is not yours. It belongs to HMRC.

How much? A good rule of thumb for your first year is 25 to 30 percent. This covers Income Tax and Class 4 National Insurance contributions. If you are earning under the personal allowance (currently around 12,570 pounds), your actual tax bill will be lower. But it is far better to over-save and get a pleasant surprise than to under-save and scramble.

The mistake almost every new freelancer makes is thinking “I’ll sort it out later” or “I’ll set money aside when I earn more.” Do it from pound one. Your future self will thank you.

4. Track everything

Every receipt. Every expense. Every subscription. This is not optional. It is how you reduce your tax bill legally and accurately.

As a freelancer, you can deduct legitimate business expenses from your income before tax is calculated. That means every deductible expense directly reduces what you owe HMRC. Common expenses new freelancers forget to track:

Software and subscriptions: design tools, project management, cloud storage, accounting software
Coworking and workspace: day passes, memberships, or a proportion of your home costs if you work from home
Phone and internet: the business-use portion of your mobile and broadband
Travel: trains, mileage, flights for client meetings
Professional development: courses, books, conference tickets relevant to your work
Equipment: laptop, monitor, desk, chair
Professional services: accountant fees, legal advice
Insurance: professional indemnity, public liability if required

The key word is “legitimate.” The expense must be wholly and exclusively for business purposes. A laptop you use only for client work? Deductible. A laptop you also use for personal gaming? Only the business proportion.

Get into the habit of photographing receipts the day you get them and logging expenses weekly. Shoeboxes full of crumpled receipts in January are a nightmare. Digital records are what HMRC expects going forward, especially with Making Tax Digital rolling out from April 2026 for those earning over 50,000 pounds.

5. Understand Payments on Account

This is the surprise that catches almost every first-year freelancer off guard.

Here is how it works. You file your first Self Assessment tax return by 31 January, covering the previous tax year. You pay your tax bill. So far, so expected. But if that bill is over 1,000 pounds, and for most freelancers earning a decent income it will be, HMRC then requires you to start making Payments on Account for the following year.

Payments on Account are advance payments toward your next tax bill. HMRC assumes you will earn roughly the same this year, and they want half up front. Each payment is 50 percent of your previous year’s bill, due on 31 January and 31 July.

Here is where it stings. On that first 31 January, you do not just pay your tax bill for the year that just ended. You also pay the first Payment on Account for the current year. So if your first-year bill is 4,000 pounds, your total payment on 31 January is actually 6,000 pounds: the 4,000 you owe plus a 2,000 advance. Then another 2,000 is due on 31 July.

Nobody warns you about this. Plan for it. If you have been setting aside 25 to 30 percent from day one, you will be fine. If you have not, this is where freelancers get into trouble.

6. VAT: probably not yet, but know the threshold

The current VAT registration threshold in the UK is 90,000 pounds. If your taxable turnover exceeds this over any rolling 12-month period, you must register for VAT within 30 days and start charging it on your invoices.

Most first-year freelancers will not hit this number. But it is worth knowing about for two reasons. First, so you are not blindsided if your business grows faster than expected. Second, because it is calculated on a rolling 12-month basis, not the tax year, so a few very good months can push you over even if your annual average is lower.

If you do approach the threshold, talk to an accountant. Voluntary registration can sometimes make sense even below the threshold, depending on your clients and expenses. But that is a second-year problem for most people.

7. Common first-year mistakes

After talking to hundreds of freelancers, the same mistakes come up again and again:

Not setting aside enough for tax. The most common and the most painful. You cannot negotiate with HMRC. The bill is the bill. Set aside 25 to 30 percent from every invoice and treat it as untouchable.

Not tracking expenses. Every untracked receipt is money left on the table. You are paying more tax than you need to. This is especially true for home office costs, travel, and professional subscriptions that people forget are deductible.

Registering with HMRC too late. Penalties exist for a reason. Register early, not at the last minute.

Not understanding Payments on Account. The doubled-up January bill has caused genuine financial hardship for freelancers who did not know it was coming. Now you know.

Spending inconsistent income consistently. A 5,000-pound month does not mean you earn 5,000 pounds a month. Freelance income is irregular. Build a buffer. One good month does not change your baseline.

Ignoring National Insurance. You will owe Class 2 and Class 4 National Insurance on top of Income Tax. This is included in your Self Assessment bill, but new freelancers often only think about Income Tax when estimating what they owe.

8. Tools that help

You do not need to do all of this with a spreadsheet, though some people prefer to. There are several options:

For accounting and tax returns, tools like FreeAgent, Xero, and QuickBooks are popular with UK freelancers and integrate with HMRC for Making Tax Digital.

For the daily question, “how much of this money can I actually spend?”, that is where Nett comes in. It is designed to calculate your Safe to Spend after setting aside your estimated tax reserve automatically. You log income, track expenses, and Nett shows you what is actually yours. It is built specifically for freelancers who are tired of guessing whether they can afford things.

You can scan receipts with your phone, and it handles the categorisation. No accounting degree required.

What now?

You have the knowledge. The rest is just building habits. Register with HMRC this week. Open that separate bank account. Start putting 25 to 30 percent aside today. Track your expenses as they happen, not three months later.

Your first year will have plenty of uncertainty, new clients, changing rates, figuring out your workflow. Your finances do not have to be part of that uncertainty.

Join the Nett waitlist and be the first to take the guesswork out of what you can spend.