Temporary self employment- what do I need to know?

[TheCuddlyOctopus]

I'm leaving my current job next week and am going to do some contracting for a former employer and one other client while I wait a couple of months to start my next job. I'm already registered for self assessment due to child benefit.

For my main client I will be paid through Comensura, a client management firm and tax and NI will come off at source.

I'm guessing I also need to register as self employed as well as for SA?
Anything else I need to know (apart from keeping all my receipts)?

Client 2 (and maybe a 3rd client) will probably be about 5k max - ideally I'd like not to be hit by paying a proportion of tax for the following year when I do my tax return as I'll be back on PAYE by then- do HMRC allow for this?

Any advice welcome! Planning on perm self employment in a couple of years and at that point will set up as a company etc.

For my main client I will be paid through Comensura, a client management firm and tax and NI will come off at source.

That is employment not self employment.

Assuming you mean payments on account for the next year, you will have to estimate your tax and apply to reduce the payments on account if you think your actual tax liability will be lower than the automatic POAs computed.

Thanks, that's helpful on the POA. Am checking the employment status- am going to be submitting timesheets and invoicing but I think it's also new to the client so they;re getting back to me.