When do I have to tell employer of maternity leave dates?

[mytime777]

I've read that I have to inform them no later than 15 weeks before Mu baby is due. It's 18 weeks until my due date now. I have my next appointment with my midwife on 4th sept when I was told I'll etcmy MAT b1 form.
By the time I get that it will be less than 15 weeks before due date. Do I have to wait for my form or can I tell them before hand?
Also are u allowed to change ur mind as to how long you want off as ideally I'd like the full year off but were not sure we will be able to afford it so may have to go back at the end of the 36 weeks ( when mat pay stops)

Any help or advice would be helpful :-) x

You don't have to have your MATB1 before you tell your employer - you can give them the form afterwards.

You can change your mind but you must give your employer at least 8 weeks notice in writing if you want to do something different from what you originally notified them.

Don't forget if the baby's dad is planning on taking paternity leave he needs to give 15 weeks notice too. I only twigged this when someone on here mentioned it!

This is all set out really clearly on the direct.gov.uk website, there's even a calculator which ends in a template calendar and letter, useful. You can tell your employer any time, the MAT B1 is their official record, used for payroll.

Always tell your employer you are planning to take the full year (they are supposed to assume this anyway) and if you want to return before that, you just give them 8 weeks notice of the date you want to return on.

You officially need to tell them by 15 weeks before your due date (and DP needs to tell his work by 15 weeks before too) for you to be able to claim maternity and paternity allowance so don't miss this deadline. The MatB1 form can be handed in later. Dates can usually be changed from what you initially put - just check with your HR dept how much notice they need. I would tell work now just so you don't leave it too late as DH forgot to tell his work by the deadline! Luckily they were ok with it, but I think they could have refused to pay paternity leave if they were sticking to the rules.