Support queriues inc. MTD Fetch/API queries

We are experiencing a lot of calls with respect to MTD Quarterly Filing and waits times are longer than usual. We are updating details within MTD Quarterly Filer - Known Errors for the common messages seen. Alternatively please email us on support@taxaclc.com where a member of the team will pick this up as soon as possible. Please note there are HMRC link:  no penalties for missing a quarterly update deadline for the 2026 to 2027 tax year.

  • Resources
  • Getting started with Self Assessment

Getting started with Self Assessment

This series of short videos will walk you through the full process from installation to completing and filing your Self Assessment tax return. 

How to download TaxCalc to a new computer

How to update TaxCalc

How to file your Self-Assessment tax return

How to import a previous tax return

How to import multiple tax returns

How to create a PDF copy of your return

How amend a preciously filed tax return

How to locate a missing tax return

FAQs

Specific scenarios

Some income types are treated in a specific way - we address some of these here.

Troubleshooting

If you encounter an issue when using TaxCalc check out our Knowledge Base
or these common questions below.

Take the next step

TaxCalc can support you with everything from Self Assessment tax returns to quarterly filings for MTD, suitable for individuals, businesses, trusts and partnerships.