Re: I'm with 123reg
Nope. When you transfer to another registrar you pay the fee (which is similar to a yearly renewal fee, often a bit cheaper because bait) and you get a year added on until the domain expires.
Not with the group I normally use (1stdomains.co.nz), at least not when I last transferred someone to them, which was a year or so back. You only pay when you register or renew, and if you transfer an existing domain to them you don't have to pay until renewal (or if you want to use some of their other services). Of course, they could've changed that since then, and of course this may be fairly unique to them.