When can they eat layer pellets?

[new2chickens2011]

Hi all,
my four girls are 18 weeks old. They were on chick starter since aside from layer pellets thats all I could find here. My last bag just ran out today. They aren't laying yet, but can I give them layer pellets anyway? Or should I just buy another 25 lb bag of chick starter (smallest I can find) even though they will probably start laying before I use it up?
Thanks!

 

[Yay Chicks!]

18 weeks is fine to start them on Layer.

 

[new2chickens2011]

Thanks!