Dishonest mothers help or am I to blame?

No contract? Just let her go. Don't engage with her.

Get tid and report her for tax fraud.

I never give tax advice without an engagement letter & full info disclosed, but it's a lot more nuanced than you have described. It's about the flexibility & control within the relationship. If in doubt speak to a chartered accountant or seek advice from HMRC.

Tell her that her services are no longer required and repeat your understanding that she was self employed and provided services to you on an ad hoc basis only. If she pushes back seek advice from HMRC to clarify her status and correct anything required from your end. She will have to do likewise including repaying the taxable element if appropriate. I suspect she will very quickly back down as that won't suit her. It's helpful that you have it in writing that you agreed £21 gross and she happily accepted gross payments until now. Then next time you'll know better.

As other posters have said, it is a bit of a grey area. Nannies can't usually choose to be SE even if they would prefer that. But the fact that she works for at least one other family and seems to control her own availability to you (you ask for certain hours but she chooses to leave early or miss days if it doesn't suit) are factors more applicable to SE.

I once had a "nanny" like this. She had previously worked as a childminder for us (definitely SE) but when she gave up formal childminding she carried on doing a few hours a week for us, looking after our kids at our house. She insisted she was SE and didn't need an employment contract and it was ok because it was "babysitting" not "nannying" (the hours and times of day just about fitted the criteria for babysitting) and she also did babysitting for another family and gave piano lessons. I grew increasingly uncomfortable about this due to the aspect of "recurrence" (similar hours every week) and because we still paid her if she missed weeks for sickness/holiday (she was a single mum and we wanted to help). In the end I brought the arrangement to a close because I felt the longer it went on the worse it would look for me if HMRC looked into it but she definitely rebuffed any attempts to formalise the arrangement.

Too many people think being S/E is something you can just mutually agree.

Legislation expects you to apply PAYE (as an employer) for as little as one day's work.

Professionals just about get round it (bookkkeepers etc) if they have a roster of clients they visit.

Don't forget other factors like having a company email address, or regular office to use can also point to employment.

(no particular experience of the "mothers help" angle though..)

Nannies explicitly cannot be self employed. I would suspect the same would apply to a mother's help. One test of genuinely self employed is whether she could send someone in her place?

She is taking the piss, and dont pay anything sack her, if she plays up report her to the HMRC. If she is stating her own rates she is self employed, a employee would take the wages offered and leave if it wasn't what she wanted

In future don’t pay anyone who doesn’t issue you with a proper invoice. If they do issue an invoice, it would be a reasonable assumption on your part that they are indeed self employed

Don’t be ridiculous- I also choose my cleaners hours. She is absolutely self employed.

Reporting her to HMRC would be a double-edged sword as OP is possibly also defrauding HMRC

I'm not looking for tax advice myself, but perhaps OP needs to do this before resuming the current arrangement or starting a new one.
FWIW, I think that my employer was erring on the side of caution, but I was glad to be put on the payroll as it meant getting pension contributions and so on, and less detail to fill in on the tax return.

HMRC likely wont do much to her gor the few hours shes done as theres a threshold she has to hit.

But id text stating your understanding re: her being self employed

I also wouldnt call it sacking her. Id just say, I need no hours this week or for the foreseeable. And let her crack on. She wont get anywhere

I dont know how you can want this woman in your home.
At this point id let the chips fall where they may...

I'd be clear the relationship has broken down due to her poor communication and inability to work the agreed hours (regularly leaving early and being paid for time not present) and I'd put that in writing now so if it goed anywhere you have a "counterclaim" so to speak.

I think he should go back to his Mum and say he's happy to stay for the figure of £500 per month - put the ball back in her court. There's a big difference for her between £500 a month and Zero money per month. She might change her mind and the whole situation will be resolved.

You have no contract, she doesn’t have a leg to rand on. Terminate her employment which you can as no contract. If you get a new nanny make sure you get a contract with expected hours/pay/etc. self employed people do not get sick pay or holidays but do earn more per hour.

If you know about self employment then why didn't you properly follow the rules about SE for this woman?
I assume as a Freelancer you have insurance etc and invoice your clients and have proper contracts with them so why did you get it so wrong with this woman?
Yes she is a chancer but you have not really done things correctly yourself either

Change the locks - seriously- then text her that your working relationship has broken down and you won't be needing her again. She can complain to acas or whoever if she wants, it will be easier to deal with them in the unlikely event that they support her.

Drop her like a hot potato .......... she will only continue to cause you trouble.

Time to change the locks - pronto.

Hang on if she has no contract and nothing in writing then surely she has no more ability to prove you owe her money then you have to prove she said she was self employed. I mean I know nothing about this area but in theory this would be no different to hiring a casual babysitter. She can’t decide after the fact she wants anything different and then make you pay it as there was never a written agreement you would pay her in the first place. Treat her new message as a change in terms say you don’t agree and let her know you no longer need her services. Also she is not entitled to full sick pay without a contract. I have only ever had one job with full sick pay otherwise it is all stat pay. Also yes maybe everything I have just said is garbage so apologies if that’s the case.

@Newmama2222 if she has been employed by you for less than 2 years you can still terminate saying the role is no longer required without an consequences. This changes in 2027.
Pay her (+ notice)
then tell her not to return, change locks
Do not make this mistake again

If you do this it could be seen that you are admitting she is employed, this could cause issues with HMRC

No contract, nothing substantial in writing.
Bin her off. Let her do her worst.
She will only be making trouble for herself.

You are not fucked She is.*