How do I file my self-assessment tax return on the online HMRC portal as a self-employed person?

This document relates to the short version of the self-assessment tax return (SA103S), suitable if your annual business turnover was below the VAT threshold of £85,000 for the tax-year.

We’ve made it easy for you by mapping the HMRC boxes with the relevant categories in the Countingup Profit and Loss feature.

You need to make sure you’ve used the correct categories for all your transactions in that tax year. You can find explanations of these categories here. If you’re unsure, we recommend speaking to a bookkeeper or an accountant.

If you have business transactions that have been incurred outside of the Countingup app, make sure to input them in the app by using the sales invoices and bills features. Your accountant can also do this if you give them access to your data by using the Countingup Accountant Hub. See how to give them access here.

This document recommends mappings of transactions recorded in the Countingup app to the HMRC self assessment return.  Countingup accepts no responsibility for an individual's tax return, it is the individual's responsibility to ensure no data is omitted from the return and data is entered accurately and appropriately within the app and return.

Let’s get started

Sign in to the HMRC online portal to start filing your tax return here. You can save a draft at any time to submit it later.

The HMRC online tax return is made up of these sections: 

You can find explanations on how to file it here. 

When you get to the section ‘Fill in your return’, some parts highlighted below can be completed by looking at the data in your Countingup app.

Note that the Countingup application records your bookkeeping data on an accrual accounting basis. If your accounting records are calculated on an alternative basis, such as on the Cash Accounting Scheme, the Countingup application will not consider this.

Now open your Profit and loss report in the app

1. Go to the ‘Accounting’ tab
2. Select ‘Profit & loss’
3. Select the tax period you are preparing the tax return for

Use below mapping to complete ‘Income’ and ‘Expense’ section