The figures you enter stay in your browser. What the site does record is a little about each visit, and your email only if you give it.
Every figure you type into the projection is calculated in your own browser. Your salary, your balances, your pension, your children's ages and what you spend are never transmitted, and there is no account to create. The code that does the arithmetic makes no network requests at all.
When you press Save this plan, the plan is written to your browser's local storage on that device, and it stays there. Clearing your browser data deletes it, and nobody else can read it, me included. Nothing else on the site writes to your device. That is also why a plan does not follow you from your laptop to your phone. To move one, use Export plan as CSV in the tool's ⋯ menu and import the file on the other device. The file is yours, and it goes wherever you put it.
Three things are recorded, and none of them contains a figure you typed.
?ref=contractoruk or ?utm_source=contractoruk,
one row is written to the same database as the email list: the tag, the page
you landed on and the time. This happens whether or not you sign up. Each
arrival is recorded once; a reload, the back button or a click from page to
page is not counted again, and nothing is stored on your device to manage
that. Untagged visits are never recorded there. It is how I tell which post
was worth writing.Beyond those logs, the only personal data this site collects is what you type into the sign-up box or the request form below, and only when you press the button. The sign-up comes in two steps:
Your email is used to send you one short note after each Budget or new tax year, saying what changed and whether it moves your salary vs dividend split, and nothing else. What you tell me in the second step is used only to understand who is interested. None of it is sold, shared or added to any other list. The lawful basis is your consent, which you can withdraw at any time by replying to any note, or by asking as described below.
The list is held in a Supabase database, and the site itself is served by Vercel. Both are suppliers processing data on my instructions rather than their own. Both are US companies, and the database is held in the United States; the transfer out of the UK is covered by the Standard Contractual Clauses with the UK International Data Transfer Addendum in their data processing agreements. Sign-ups are kept until you ask for yours to be removed, or until this project stops, whichever comes first.
You have the right to a copy of what is held about you, to have it corrected, to have it deleted, and to object to it being held at all. Ask by email or with the form below, and it will be done. There is no verification hoop beyond proving you have the address in question. If you are unhappy with how that goes, you can complain to the Information Commissioner's Office at ico.org.uk.
Aftertax is built and run by Tom, one person in the UK. That makes me the controller of the email list described above: the person responsible for it, and the one who acts on any request about it. Email aftertax.xyz@gmail.com, or use the form below, and it will be dealt with within a month, which is the legal limit, and usually within a few days.
What the form sends (your email address, what you are asking for and your message) is held in the same Supabase database as the email list, used only to answer the request, and deleted automatically after 90 days.
If this page changes in a way that matters, the date below changes with it. Last updated 25 September 2026.