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Adsum

By Adsum
4.97 out of 5 stars
Provider of InstantVAT and OpenTax, delivering smart solutions to simplify tax management.
Rated
5.0
out of 5
Reviewed by
100
Xero users
Listed for
3 years
August 2022
Key functions
Payments

Overview

About Adsum Adsum is a leading innovator in digital tax solutions, offering smart tax compliance tools for accountancy practices and accelerated tax refund payment solutions for businesses.

InstantVAT - for businesses No company should have to wait days for their VAT refunds. And now they don't. Simply sign up and start receiving your refunds in as little as 24 hours.

OpenTax - for accountants & bookkeepers Tax management, simplified. Save time and optimise workflows by tracking all your clients' tax obligations and liabilities in real-time from a single dashboard.

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Adsum + Xero

Adsum works seamlessly with Xero. Connect your Xero account with one click and join the 1,500+ businesses benefitting from our services.

Reviews & ratings

5.0 out of 5 stars
100 Reviews

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Most recent reviews

DB
Darren Buckley
Posted 24 Oct 2025
5 out of 5 stars

An Accountants Dream!

An immensely intuitive solution that powers accountants to be the proactive advisor their client needs when it comes to tax compliance. Having this single platform to connect our agent accounts has meant we are able to spot any issues way before the fact, saving them from potential penalties.
LG
Luke Green
Posted 24 Oct 2025
5 out of 5 stars

Really Helpful Tool

The OpenTax feature gives a great overview of our clients tax affairs and allows us to be proactive with clients advising when taxes are becoming due and overdue. This is an app that definitely provides useful time saving opportunities and increases proactiveness when advising clients!
MC
Michael Cloke
Posted 23 Oct 2025
5 out of 5 stars

Intuitive and helpful tool

Opentax is a really helpful tool for seeing everything in one place. It simply doesn't exist on HMRC (or anywhere else that I've found for that matter) so it's a great overview on all the tax positions for all of our clients all at once and I'm excited to see how they keep building out the agentic AI side.

Additional info

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Industries

Professional servicesAccounting

App details

By Adsum
Added in 2022

Get started with Adsum

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