How to use this chart
Find the month the mare was bred in, then her breeding date in the left column. The date beside it is the expected foaling date at 340 days. For a group bred on pasture, look up both the day the male went in and the day he came out: the foaling window runs between those two dates.
The chart is a fixed 340-day count. If you want the date adjusted for your breed, plus the checks worth doing along the way, use the Horse Gestation Calculator, which also sends the dates to your phone's calendar.
Frequently asked questions
How do I use a mare gestation table?
Find the last covering or insemination date and read across for the foaling date at 340 days.
Why is my mare past the date on the chart?
A normal mare pregnancy runs 320 to 370 days, so going past 340 is common and not a problem on its own. Call your vet if she shows discharge, colic or illness.
Do mares foal at the same time each year?
Many mares repeat their own pattern, so your own notes from last year beat any chart.
When does foaling watch start?
Usually two to three weeks before the chart date: udder filling, wax on the teats and a relaxed tailhead are the signs.
Estimates only. Individual animals vary — confirm pregnancy and health questions with your veterinarian. Last reviewed 2026-10-05.