It’s a very personal choice. You need to get some real numbers in your calculation, and then chuck in a bit of thought about your personal feelings!
Look up some actual nursery fees for some settings near you that might appeal - it depends on where you are, and whether they are full time or term time (I’m a teacher, so can take advantage of doing term time only). For our DD, nursery started out as £75 per day, so I worked out a couple of scenarios - if I worked full time, if I worked 3 days a week etc. Don’t forget that it might not be as simple as scaling it - in my case I lost some responsibilities by going part time, so 3 day a week pay worked out as less than 0.6 of my full time salary, and transport also didn’t scale because a weekly train ticket is less than 5x daily fare etc. Properly work out the finances - what is the bottom line in each case? I worked it out based on my salary only because that was what we had flexibility on, but please do remember that childcare is actually a shared cost - it won’t just be coming out of your pay!
Then have a good think about how you are likely to feel. Financially, I would definitely have been better off full time and would have had more career progression. But that really wasn’t something that I wanted to do - personally I still wanted a bit more time at home with DD. So I chose part time. I didn’t consider giving up completely for 2 reasons - I wanted some adult time (coffee machines! Lunch with colleagues! Weeing on my own!) and I knew although I could definitely go back to teaching later, if have a lot less choice if I’d been out for a while. Some people aren’t fussed about career progression, or really want to have lots of time with their children so don’t want to return to work. Others feel they’re better parents at evenings/weekends if they’ve been refreshed by adult time. It’s a very personal choice and you need to think about that as well as the finances (assuming you are in the position to choose).
It’s worth having a think about what your back-up plans are in the event of illness etc - children pick up a tonne of bugs when they first start nursery! I commute, so wouldn’t be able to get back. DH is also a teacher (and even if your kid is ill, they aren’t going to pull you out of a lesson so you can go collect them!) so couldn’t necessarily come at the drop of a hat. My DMum was happy to be the emergency contact for those circumstances. Think about how that will work for your family.
If one of you does stay home at least some of the time, think about financial implications (just in case!). Taking time out of work may have an effect on long-term pay as well as current earnings, pension pot etc. Make sure that your long term interests are protected. I didn’t really bother with this because my part time pay was still as much as DHs full time pay. I do think that I have a tendency to buy stuff for DD sometimes using my own money (just don’t think otherwise!) rather than joint money, so probably have less disposable income than DH now. Getting ready for second maternity leave now and am going to think about it a bit more carefully this time!
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