At what age do chickens become fully grown?

[ZANEYchickenguy]

What age do Rhode island reds and Easter eggers reach full size (stop growing)? Or really I should be asking when are my young easter egger big enough to go out to the rest of the flock?

 

[turkey girl 0964]

IMO, about 18 weeks, when their first egg is laid.

 

[JacinLarkwell]

It's different for all breeds. Yours will be pretty much full grown by 8 months, but you don't need to wait that long to start introducing new birds

 

[aart]

What age do Rhode island reds and Easter eggers reach full size (stop growing)?

A chicken is full grown at about a year....or two.

Or really I should be asking when are my young easter egger big enough to go out to the rest of the flock?

Two different things^^^

Integrating can be done when chicks are young....or later.
Either way don't expect instant 'love'.