Question about transferring a domain

(I didn’t know what forum to put this in, so you can move it if it’s in the wrong place)

Does anyone have experience with transferring a domain from one web host to another? How long did it take to get the site up and running on the new server?

I was told two different things, by the two different hosting companies. One said 1-3 days, the other one said it can take weeks.

thanks.