When does a penis stop growing?

Penile growth: It is generally accepted that penile growth stops after puberty. www.peedoc.com @drhtay.

After puberty: After all your pubertal changes have concluded: hair growth, height growth, penis growth, etc. Since i don't know your age, i can't tell you if any further growth is possible.

After puberty: The penis obtains its full adult length at the end of puberty, in the mid to late teenage years. And remember, erect penile length varies far less among individuals than does flaccid (limp) length: http://theturekclinic.com/penis-size-erections-length/

Penile growth: The penis should have reached its full adult size by age 21 years old (unless one entered puberty late). See: http://www.nhs.uk/Livewell/penis-health/Pages/penis-size.aspx