I was about to correct you that in the U.S., the starting PTO might be more like 10 or 15 days...but then remembered that this is all in the UK. (Man, i really dislike the U.S.' version of capitalism.)

Otherwise, great inputs on the costs you referenced; cheers!

I also bundled in "sick" with "personal" and "vacation" because I've seen US companies do away with all of the distinctions and just say "here's 20 days a year, do what you want with them. You'll get more next year."

Unfortunately that's pretty common. Old-line companies (including in tech) often still have the sick-time/vacation distinction but my impression is that it's relatively uncommon in newer companies. It has to some degree been replaced with "unlimited" vacation but that comes with its own set of issues.

What issues does that come with, in your opinion?

There isn't a defined number of days that you're "entitled" to. Not that the entitlement is always taken or that people always feel comfortable taking it, but at least it's there. (And, personally, I've essentially always taken my earned vacation.)

I don't necessarily have a problem with unlimited/unmetered vacation. It means you don't get a payout if you leave a company but I don't really have a problem with that. However, I do think it puts the onus on management to set clear and reasonable expectations around vacation--which hopefully are what I would consider reasonable.

If I were to entertain an offer with an unlimited vacation company, I would expect HR or the hiring manager to be able to answer the question: "Is 4-6 weeks of vacation considered reasonable?"

ADDED: I'm not complaining about downvotes but I'm genuinely curious what someone finds objectionable or controversial about this comment.

Not parent but unlimited vacation policy is often criticised as a way to bully people into taking even less vacation. Since you can’t know how much is “okay” you end up in a guilt trip if you take more than some colleague.

Hence my point that there needs to be clear top-down setting of expectations. If you have company management that looks on "unlimited" vacation as a way to avoid having to pay out accrued vacation if an employee leaves combined with a way to grudgingly allow a day off here and there when it's convenient for the company... That's going to be a very bad fit with an employee who sees it as an opportunity to take a couple months off every year.