Self-assessment Software for Accountants

Our self-assessment software has proven invaluable for accountants looking to weather self-assessment season and complete every clients’ tax return on time with a faultless tax calculation.

Tailored to your requirements and recognised by HMRC, you can use Capium to serve your clients — from sole traders to company directors — with the speed and accuracy that accountants a decade ago could only dream of.

Self-assessment Software that makes Tax Return submissions a breeze

“Self-assessment returns have never been easier.
“Capium’s cloud-based software supports everything you need to produce and submit tax returns, drawing from your bookkeeping data for accurate results and maximum efficiency.
“With no limit on staff user licences, your whole team can use it, and our support team is on hand to help with any challenges along the way.“
“Oh, and did I mention that you’re entitled to a 7-day free trial, so you can test whether Capium’s self-assessment software is right for your practice?”

Self-assessment tax return software that saves you time and energy

With our digital self-assessment system, you can get a clear overview of everything on your plate. Never lose track of an important task again.

Seamless integration with HMRC

Recognised by HMRC, use our software to send your clients’ returns with one click of a button in no time at all.

Keep track of your submission status

View the submission status of every tax return you send, giving you peace of mind it’s with HMRC ahead of the deadline.

SA100, SA800 and SA900 forms supported

Auto-generate and submit the correct forms to HMRC for sole traders, partnerships, trusts and estates.   

Self-assessment software designed by accountants

We used to be accountants, so we understand the sector’s struggles. That’s why you can trust that our software will deliver everything you need to accurately create and process every client’s tax return on time.

No limits on tax returns sent

Process as many returns as you need to for your clients, with no cap on the number you can run through the system.

Easily submit supplementary forms

Auto-generate and submit supplementary pages to easily tell HMRC everything about your clients’ income.

Enhanced error warnings and handling

Capium flags potential errors so you can review, adjust and confirm returns with minimal disruption.

API integration with HMRC To produce SA100 returns with ease

Futureproof your accounting practice

From MTD to GDPR, we anticipate and respond to the future so your practice can operate with confidence.

Integrates With Other Capium Software

Our self-assessment software updates your data across the rest of the Capium suite, eliminating the need to enter data twice. 

GDPR Compliant

Your clients’ sensitive data is safe with Capium. We’ll keep you compliant with the latest data protection legislation.

Become MTD Ready

Create MTD systems without congestion or disruption. Capium is recognised by HMRC as an MTD supplier.  

Prices as low as £18 per month for 100 clients

Frequently Asked Questions

No! You are charged on the number of clients you run through the system — not the number of returns. 

You can track your submission status in real time as we receive live feedback from Companies House. You can also contact our support team by phone or email. 

Of course! As former accountants, we understand the hassle of having to use different approaches for different clients. To that end, we’ve perfected our SA900 submodule for partnership returns.  

Absolutely! Our software lets you pull through client data and auto-generate supplementary pages for additional income, including capital gains. 

Yes! We offer free support to all our clients. Our support team is available by phone from 8am to 6pm during weekdays, and from 10am to 4pm on Saturdays. Alternatively, send us an email, and we’ll get back to you as soon as possible!
Interested in what you’ve read so far? Take the next step and get in touch with us, or try our self-assessment software for yourself with a 30-day free trial.
Our self-assessment software has proven invaluable for accountants looking to weather self-assessment season and complete every clients’ tax return on time.

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