Terms of service

Last updated 1 October 2026

1. Who these terms are between

These terms are between Open Systems Software ("we", "us") and the business that signs up for Kassa ("you"). Kassa is sold to businesses only. By creating an account, installing the till or paying for a plan, you confirm that you are acting for a business and that you can agree to these terms for it.

The software licence that comes with the installer also applies. If it and these terms disagree, these terms win.

2. Plans and payment

Plans are priced per shop per month, as shown on the pricing page when you sign up. The Starter plan is free. Paid plans are billed monthly in advance.

We are not registered for VAT, so no VAT is added to our prices. If we register for VAT, we will tell you at least 30 days before VAT appears on an invoice.

We can change a plan's price by telling you at least 30 days before the change. If you don't want the new price, you can cancel before it starts.

If an invoice is unpaid 14 days after its due date, we can move the shop to the Starter plan until it is paid. The till keeps selling. Paid features stop.

3. Cancelling

There is no minimum term. You can cancel a paid plan at any time by email. It stops at the end of the month you have paid for, and we don't refund part months. The shop then drops to the Starter plan.

You can close your account completely. We then delete your data from our cloud servers within 90 days, except what the law requires us to keep, such as our own invoices to you. Data on your own tills and back office computer stays with you.

4. What you are responsible for

Kassa is a tool. The business decisions and the legal duties of your shop stay with you. That includes:

  • Your VAT, tax and accounts. Check the VAT rates set on your products, check every figure before you file a return, and keep the records HMRC asks for. Kassa's reports and exports help, but they are not tax advice and we don't file anything with HMRC for you.
  • Age-restricted sales. Kassa prompts for Challenge 25 and keeps a refusal log. Whether to sell is decided by the person at the till, and your premises licence and its conditions remain yours to keep.
  • Prices. Feeds from wholesalers and the AI features propose changes. Nothing changes a price until someone at your shop accepts it, and you are responsible for the prices you accept and display.
  • Backups of the computers in your shop. Your tills and back office keep their own database. We back up the data that reaches our cloud servers, not your computers.
  • Your staff and your customers' data. You decide what you record about them. See section 8.
  • Keeping passwords and device keys private, and removing staff who leave.

5. Using Kassa

You may use Kassa for your own shops, on the number of shops your plan covers. You may not resell it, copy it, take it apart to find out how it works except where the law allows that, or use it for anything unlawful. Resellers need a separate written agreement with us.

Kassa and its name, look and code belong to us. Your data, your logo and your content belong to you. You give us permission to store and process them only to run Kassa for you.

6. Services from other companies

Some features connect to other companies: card terminals, online payments, age-verification checks, the hosted AI option, email delivery and map tiles. Their own terms apply to you when you turn them on, and they may charge you directly. We are not responsible for their services, but we will help you if one stops working with Kassa.

Names of wholesalers, payment companies and other businesses appear on our site and in Kassa only to say what Kassa works with. They are the trade marks of their owners, who do not endorse Kassa.

7. Availability and changes

The till keeps selling when the internet or our servers are down, and syncs when they come back. We aim to keep the cloud dashboard running all the time, but we don't promise it will never be unavailable. We will tell you in advance about planned work when we can.

We improve Kassa often. If we remove a feature that is part of your paid plan, we will tell you at least 30 days before, and you can cancel without paying for the following month.

8. Your data and data protection

For the personal data your shop records in Kassa (your customers, your staff, refusal logs and online orders), you are the controller and we are your processor. The data processing terms form part of these terms and set out what we do with that data. Our own use of personal data is described in the privacy notice.

You can ask us for a copy of your data from our cloud servers at any time, in a format other software can read.

9. Limits on what we are liable for

Nothing in these terms limits liability for death or personal injury caused by negligence, for fraud, or for anything else the law does not allow to be limited.

Otherwise, we are not liable for lost profits, lost sales, lost business or goodwill, or any indirect loss. Our total liability to you in any 12 months is limited to the amount you paid us in those 12 months, or £100 if that is more.

Kassa is supplied for business use. The terms implied by statute about quality and fitness for purpose are excluded as far as the law allows. We will fix faults you report to us within a reasonable time.

10. Ending the agreement

You can end it at any time as described in section 3. We can end it with 30 days' notice, or straight away if you seriously break these terms or use Kassa unlawfully. When it ends, you can still export your data for 30 days.

11. Changes to these terms

We will email you at least 30 days before a change that affects you. If you don't accept it, you can cancel before it starts.

12. Law

These terms are governed by Scots law, and the Scottish courts deal with any dispute. Before going to court, we both agree to try to settle it by talking first.

13. Contact

Email opensystemssoftware@gmail.com. Post: 2 Taylor Place, G4 0NY, Glasgow, Scotland.