Thanks.

I should have put this in my post.

I have to tell them at some point so I can arrange paternity leave. In the UK you have to have worked for your employer continuously for at least 26 weeks by the end of the 15th week before the expected week of childbirth to get paternity leave[1], and holiday allowance for new employees is usually pro rata based on number of months worked, so I won't be eligible for paternity leave or have much holiday allowance by the time the baby is due. So before I accept an offer I need to know that they will be flexible about taking unpaid leave.

[1] https://www.gov.uk/paternity-pay-leave/eligibility

> So before I accept an offer I need to know that they will be flexible about taking unpaid leave.

Just as long as you understand that some (many? most?) employers will not hire you once you tell them this.

Which is why I'd wait until they make an offer as they are less likely to back out at that point as they've already made the decision to hire me whereas they might (even subconsciously) take it into consideration if I tell them before.

Also, getting offer is valuable information on what my current market rate it.

If you are going to take unpaid paternity leave and this is your first child I would go down the ignorance route. Treat the whole thing as an "unexpected" medical emergency where you have to take time off because your wife/partner needs you. You can do this with little notice and if you plan ahead you can turn the whole thing to your advantage by making the effort to make sure everything continues in your absence. Check in, send lots of baby photos, and don't let the team down and you will look like a hero.

I'm not exactly sure how one would spin childbirth as "unexpected".

"Whoops, turns out my wife was pregnant for the past nine months, who knew?"

The childbirth might not be unexpected, but the need to take time off would be. The op can credibly claim he did not intend to take anytime off at all and it is only because wife needs him and this was unexpected.

I think you're setting a precedence that it is you vs company. If you're upfront and they work around this or even embrace it, you know they are a good company to work with.