Yes. On a paid plan it is built for business use, and on Team, Business and Enterprise your chats stay out of model training by default. The care is in what you paste in and who checks what comes out.
Below: what it is good at, what to keep out of it, what a business brain is and what you can safely let AI do, and the question people ask us most, which is how to get an unpaid invoice paid.
Quotes and proposals from your own notes. First drafts of emails. Turning a call into a list of actions. Tidying a spreadsheet. Writing a job advert. Answering questions about your own documents, once you have given it the facts.
It does not know what is happening in your business today. It cannot see your invoices, your inbox or your pipeline unless you connect them. Ask it who owes you money and it will guess. Connect your accounting software and it can answer.
On Team, Business and Enterprise plans your content is not used for training by default. Strip anything you do not need. Keep bank details and health data out. Write one page of rules for your staff on what may go in, and check your customer contracts if any of them say the data stays in the UK or the EU.
Only if you want it to act on your systems. Reading and drafting is the chat window. Watching the books overnight, writing the chase and queueing it for your approval is a job for something connected. See what Harness does.
A memory of how your business actually runs, kept outside the chat window and built from your own systems. Who pays on day 40 and who pays on day 3. Which quote went quiet. What you promised, and when. How you sound when you write to a customer. Every fact carries its source, so you can check it, correct it, export it or delete it.
Harness by Heoka is a business brain for small UK firms, built as an approval layer for unpaid invoices, quiet quotes and the mail waiting on a reply, from your mailbox and your Xero. You connect the ChatGPT or Claude account you already pay for, Harness gives it a memory of your business and work to do overnight, and you approve each draft before anything goes out.
Read, sort, remember and draft. Keep send, pay, edit and delete with a person. The test: if it got it wrong, could you undo it before a customer saw it? Drafts pass. Sends do not. That is why Harness waits for your tap on every one.
Yes, if you connect the mailbox through Google's or Microsoft's own permission screen and the tool only reads and drafts. It should know who already replied, what was promised and how you write, and put the reply in the original thread. It should never send on its own, never delete or archive, and never train a model on your mail. Harness works this way with Gmail and Outlook.
They write well but know nothing about your business today, and forget tomorrow. Harness gives them a memory built from your mail and your Xero, works through it overnight without being asked, and queues the drafts for your tap, inside the account you already pay for. If a free plugin covers you, use that first. See what the memory holds.
Chase on a fixed rhythm, not on your mood. Same ladder every time, every customer. That is what keeps it polite.
Chase the day after the due date. Short, friendly, invoice attached again. Most late payments are admin, not malice.
Name the amount and ask a direct question that needs an answer. Invite them to tell you if there is a problem. Silence is the only thing you cannot work with.
Tell them what the law already gives you, without adding it yet. For business debts that is 8% a year plus the Bank of England base rate, which is 11.75% as of August 2026, plus fixed compensation of £40, £70 or £100 depending on the size of the debt.
State the full amount including interest and compensation, and give a deadline, normally seven days, before formal recovery. Flat and factual. You are recording now, not persuading.
A formal letter stating the debt, a fourteen day deadline, and that you will start county court proceedings after it. Courts expect one. Claims up to £10,000 go through the small claims track and you can file online. Most settle before a hearing.
Every email above, word for word, is in the UK invoice chasing guide and the Late Payment Playbook.
Harness connects to Xero and your email. It works out overnight who is overdue and by how long, drafts the right rung in your tone, and puts it in a queue on your phone. You tap send. Drafts wait for you to approve, edit or skip. You can let routine reminders send on their own.
If you already pay for ChatGPT or Claude on an eligible plan, you can add Harness as a connector and ask it what is waiting. It still cannot send without you.