Published
Horses on the corridor acreage: the county has already done the per-acre math
“Residential” is defined by who lives near you, not by what zone you are in
Almost nobody reads the animal rules before buying ground for horses — they read the zoning letter and assume. The Fremont County code’s animal section begins by defining its territory, and the definition reaches much further than a platted subdivision:
“For the purposes of this performance standard only, residential lots are defined as both platted subdivision lots and residential parcels in unplatted areas where there are other residential housing units within 300 feet of the subject property boundary.”
— Fremont County Development Code, 2011 Edition (Ordinance 2011-04), §5.23, consolidated through Ordinance 2026-03. Retrieved 23 September 2026
Two very different pieces of ground are “residential” for animal purposes: any platted lot anywhere, and any unplatted parcel with a neighbour’s house within 300 feet of the boundary. Out on the corridor, that second clause is the one that surprises people — a ten-acre parcel with one farmhouse 250 feet over the line counts, and with it come the animal limits below. Ground with no housing within 300 feet sits outside this performance standard entirely.
The numbers: two large animals or ten small ones, per acre
“The keeping of livestock on residential lots shall be restricted to two horses, pigs or cows, or ten llamas, sheep, or goats (including their offspring until weaned) per acre. If the maximum animal count of all livestock meets or exceeds 250, the requirements of 5.18 shall apply. No livestock shall be kept on lots of less than one acre. Keeping of pack animals during local big game hunting seasons shall be permitted for up to seven days.”
— Fremont County Development Code, §5.23.010. Retrieved 23 September 2026
The structure is cleaner than it first looks:
| Rule | Number | What it means on the ground |
|---|---|---|
| Large animals | 2 per acre — horses, pigs or cows | A 5-acre residential lot tops out at 10 horses |
| Small animals | 10 per acre — llamas, sheep or goats | Offspring count until weaned, then they are inventory |
| Minimum lot size | 1 acre | Under an acre, no livestock at all on a residential lot |
| The CAFO cliff | 250 animals | At 250 head the operation falls under §5.18’s confined-feeding requirements — a different regulatory universe |
| Pack animals | 7 days during local big game seasons | The county deliberately makes hunting-season strings legal |
Two details reward a second read. “Including their offspring until weaned” — a breeding operation does not get to argue the lambs are free; they count against the ten from day one, then keep counting after weaning as grown animals. And the 250-animal cliff is not a housing rule but a feedlot rule: cross it and §5.18 applies, the county’s confined animal feeding standards, with all the separation and waste machinery that implies.
Fowl: the separate arithmetic
“The keeping of 30 males (roosters, drakes, ganders, etc.) and hens per acre shall be permitted. Lots of less than one acre may keep fowl proportional to 30 males and hens per acre.”
— Fremont County Development Code, §5.23.020. Retrieved 23 September 2026
Note what the fowl rule does that the livestock rule does not: it scales below one acre. Livestock needs a full acre before the first horse; chickens do not — a half-acre residential lot may keep fifteen, a quarter-acre seven or eight, proportionally. The stated cap of thirty per acre includes the roosters, drakes and ganders in the same count, wording that reads as written — the males are not a bonus layer on top of the hens.
Where this leaves the Ashton corridor buyer
- The horse-property search has a legal test, not just a fencing test — and it is acreage times two, on ground that is “residential” under the 300-foot definition or platted.
- The hunting operation is planned for. Seasonal pack animals for up to seven days during local big game seasons are expressly permitted — the county wrote the corridor’s hunting economy into the rule.
- 4-H families should do the weaning math. A project pen that breeds adds animals the permit arithmetic already counts.
- Ground that is genuinely remote sits outside §5.23 — no housing within 300 feet of the boundary, unplatted, and the performance standard does not reach it. The agricultural ground being protected from speculation is a related but different machine: the agricultural protection area application is its own paperwork.
One boundary note: these are land-use numbers, not well or septic numbers. Acreage that legally supports ten horses still has to support them water-and-wastewise — the well and septic questions come first, and animal pressure on a drainfield is a siting problem even when the animal count is legal.
Before you shop ground for animals
- Measure from the parcel boundary: is there housing within 300 feet? If yes — or the lot is platted — the animal math is acreage times two.
- Count acres exactly. Under one acre means no livestock at all; fowl scale proportionally below it.
- If breeding is in the plan, budget the offspring into the count from day one — the rule already did.
- Hunting-season strings? Seven days during local big game seasons is the lawful window per property.
- Anywhere near 250 head of anything, stop and read §5.18’s confined-feeding requirements before buying another animal.
- Then call (208) 656-1516 and pressure-test the count for your actual parcel before the fencing contract.
Common questions
How many horses can I keep per acre in Fremont County?
Two horses, pigs or cows per acre on residential lots - and no livestock at all on lots under one acre. A 'residential lot' for this rule includes any platted subdivision lot and any unplatted parcel with housing within 300 feet of the property boundary.
How many chickens can I keep in Fremont County?
Thirty birds per acre counting males and hens together. Unlike livestock, fowl scale below one acre proportionally - a half-acre residential lot may keep fifteen.
Do baby animals count toward the limit?
Yes. The livestock rule counts llamas, sheep and goats 'including their offspring until weaned' - and after weaning they are grown animals still counting against the ten-per-acre figure.
Can I keep pack animals during hunting season?
Yes - the code expressly permits keeping pack animals for up to seven days during local big game hunting seasons. The county wrote its hunting-season economy into the rule.
What happens if I reach 250 animals?
The code says that once the maximum animal count of all livestock meets or exceeds 250, the requirements of section 5.18 apply - the county's confined animal feeding operation standards, a much heavier regulatory regime.
Does the animal limit apply outside subdivisions?
It applies to platted lots everywhere, and to unplatted parcels with other residential housing within 300 feet of the property boundary. Unplatted ground with no housing within 300 feet sits outside this performance standard.
Are roosters allowed on residential lots?
Yes, within the count: the rule permits thirty males (roosters, drakes, ganders, etc.) and hens per acre - the males share the thirty, they are not extra on top of it.
Where do these animal rules come from?
Section 5.23 of the Fremont County Development Code, 2011 Edition (Ordinance 2011-04), consolidated through Ordinance 2026-03 - the county's performance standards for animals on residential lots.