9 Answers

I would say no...the landlord is to return your deposit in full, unless you have damaged something.  Replacing a lock after a tenant moves out, is the landlord's responsibility.  Make sure, though, that you return the keys to the landlord, as that is part of YOUR responsibility.

Do check what your lease states, assuming that you had one.

All depends on the lease agreement you had with your landlord, I hope you had one?

Normally no, as long as you returned the keys.

I agree with the people who have answered before me. I have NEVER had a landlord withhold deposit money to pay for new locks and keys.  You DO need to return all the keys, of course, and he should change the locks anyway. 
I sure hope you don't get stuck losing deposit money for that.  There are agencies that provide free legal assistance; someone should be able to give you a reliable answer. 

If you have not damaged the lock or lost the keys, there should be no reason the landlord should use your deposit to change the locks, this is a landlords responsibility.Get in touch with a tennants advice service if he chooses to bill you, take photos of the locks also as a reference, he might say you damaged them.

No, when I had rental property I had a seperate set of lock tumblers and all I did was to reset the locks so the "old" tennant could not access the property.

At the end of the next period I swapped back to the originals ad in finitum.

Sounds like a scam to keep hold of your deposit, get legal advice.

NO. UNLESS...it was in the lease you signed OR you did not return all of the keys when you departed.

No, he can't use your deposit money to change the locks, unless it states that in your lease agreement.