I'll start by saying that DH have separate finances and it works for us. We both pay into a shared account which all household expenses come out of and leaves us with the same amount of money left over for extras (our own cars, hobbies etc).
DH and I are adopting next year and will be taking SPL. I will be taking six months at full pay and have also saved up a lot of annual leave over the years so will be off for about 10 months in total. The plan was for DH to take about 12 weeks of SPL at statutory pay, to run parallel to my leave so we are both at home together and have a better chance to bond.
I am the main earner although we both work full time. I earn about double what DH does. I also average about 7 hours a week of overtime but the opportunity to do lots more. DH rarely gets the opportunity to work overtime.
For every week of SPL my DH takes, we need £100 in savings to subsidise his statutory pay. I recently received a large performance bonus that has gone straight into savings. I've picked up a project at work which means I can get an extra 5 hours of overtime a week, which will go into savings. This means we should in theory have enough to buy all the baby bits we need as well as DH taking 12 weeks of leave.
But DH has now been asked to work 3 Sunday's between now and Christmas. He is able to have this either as overtime or as time in lieu, and he has decided to take it as time in lieu and have the Fridays off instead so he still gets two days off on those weeks. I know it's a pain only having one day off a week, but this is only for 3 non-consecutive weeks and it's pissed me off a bit that he's not taking it as overtime. The Sunday's are also only 6 hours but paid as an 8 hour day, and I work this amount of overtime every week.
I'm going to have a chat with DH tonight to see if I can persuade him to take them as overtime instead, but if not WIBU to say that I don't want my overtime and my bonus to subsidise his time off if he has the opportunity to contribute to it himself but chooses not to? I'd still be happy to subsidise 6 weeks, but I kinda feel like why should I be working my arse off for him to have 12 weeks off?
The flipside of this is that he does work hard in his job, pulls his weight with housework and childcare arrangements and is genuinely a really lovely person. Our financial situation has always been this way so we generally agree that because I'm the higher earner I pay more towards the house and pay into savings because he's not able to, his financial contribution is smaller but we are both left with equal amounts of spending money as I think that's fair.