Self Assessment
Track your personal tax returns and HMRC balance
Manage Self Assessment tax profiles, track SA returns by tax year, and calculate personal tax liability. Direct HMRC integration shows your balance, payment history, and tax calculations — all without leaving AccountsOS.
Free during Early Access - No credit card required
Capabilities
Self Assessment profile management for company directors
Track SA returns by tax year with status indicators
View your HMRC Self Assessment balance in real-time
Payment history showing all payments on account and balancing payments
HMRC tax calculation breakdown for each year
Automatic deadline tracking for SA filing and payment dates
Personal tax liability estimation based on salary and dividends
Integration with salary and dividend optimizer for year-end planning
How It Works
Connect to HMRC
Authorize your Self Assessment access via the HMRC hub. Your SA data is fetched securely using encrypted tokens.
View your returns
See all your SA returns organized by tax year — filed, pending, and upcoming — with deadlines and status for each.
Check your balance
View your live HMRC balance including payments on account, balancing payments, and any amounts due or overpaid.
Plan ahead
Use the tax calculator to estimate next year's SA liability and set aside the right amount from your company.
Use Cases
Director with dividends
Most company directors need a SA return to declare dividends. Track your filing status and see your tax calculation without navigating HMRC's portal.
Payment on account planning
Know exactly when your January and July payments on account are due, and how much to set aside from your company each month.
Year-end tax position
Before your tax year ends, estimate your SA liability based on salary and dividends already taken. Adjust remaining dividends to optimize.
Multiple income sources
Directors with rental income, investments, or other employment can see how all income sources affect their overall tax position.
Benefits
See your complete Self Assessment picture in one dashboard
Never miss a January or July payment on account deadline
Understand your personal tax position without waiting for your accountant
Plan dividend payments with your SA liability in mind
Reduce surprises at tax time with forward-looking estimates
Save time by not logging into multiple HMRC portals
Frequently Asked Questions
Do I need Self Assessment as a company director?
If you receive dividends from your company, you must file a Self Assessment return. Most UK Ltd company directors need SA registration.
Can AccountsOS file my SA return?
Currently, AccountsOS tracks your SA returns and shows your HMRC balance and calculations. Actual filing is done through the HMRC portal. Direct SA filing is on our roadmap.
When are Self Assessment deadlines?
Online SA returns are due by 31 January after the end of the tax year. Payments on account are due 31 January and 31 July. AccountsOS tracks all these dates and sends reminders.
How does this connect to my company accounts?
Your salary and dividend payments from your company flow into your SA tax estimate. This gives you a complete picture of your personal and company tax position together.
What is a payment on account?
HMRC requires advance payments towards next year's tax bill if your SA liability is above £1,000. These are due in January and July and equal half of the previous year's tax bill.
Can I see my HMRC tax calculation?
Yes. Through the HMRC integration, AccountsOS fetches your official HMRC tax calculation for each year so you can compare it against your own records.
Ready to try Self Assessment?
Get started with AI-powered accounting for your UK limited company.
Get Started FreeFree during Early Access - No credit card - Cancel anytime