When do hens typically stop laying each year?

[Grammypammy]

Five hens are just over two years and 10 that were last spring's. In the other house are 5 hens just over a year. In the house with 15 they have all stopped laying in the last two weeks. My bantams in the little coop never hardly skip a day. I sort of thought they stopped laying in February, am I wrong? Why would my girls stop now and how long does it last?

 

[Happy Chooks]

They will usually stop in the fall to molt. Have there been any changes to living arrangements - birds in or birds out? Did they run out of water? Any predator scares? Chickens hate change of any sort, so any change to their environment can cause them to stop laying for a bit.