To get rid of rats on a farm, work in this order: remove the easy food and shelter, proof the buildings against entry, then bait with locked tamper resistant stations placed along the walls, runs and burrows rats are actually using, kept in and around buildings rather than out in the open. Use enough stations, check them regularly, and clear away any dead rats. A single breeding pair can turn into well over a thousand rats in a year, so acting early is the difference between a quick job and a long one.
Farms give the brown rat (Rattus norvegicus) everything it needs in one place: spilled grain and livestock feed, water from troughs and dripping taps, and endless shelter in stacked pallets, old machinery, straw and cavities. That is why rat pressure builds fastest in autumn and winter, when food in the fields runs out and rats move in toward buildings for warmth.
The reason to act quickly is simple maths. Rats breed fast, and an unchecked pair can become well over a thousand animals inside a year. On top of the feed they eat and contaminate, rats gnaw constantly, and chewed wiring is one of the most common causes of electrical fires in farm buildings. They also carry leptospirosis, the bacterial infection behind Weil's disease, which can pass to people and livestock through rat urine, so this is a health issue as much as a cost one.
You will usually see the evidence before you see a rat, because rats are mostly nocturnal and seeing them in daylight often means the population is already high. Look for droppings (dark, around 15 to 20mm, near feed and along walls), smooth greasy smear marks where rats brush along the same runs, burrows around 70 to 120mm wide at the base of walls, banks and slabs, gnaw marks on doors, feed bags, timber and cables, and well worn runs through grass and along walls between harbourage and food. Disturbed or chewed feed sacks and missing eggs in a poultry setup are common early signs too.
Rats tend to live outside a building and come in to feed, following established routes and their sense of smell rather than their poor eyesight. On most farms they get in through gaps under doors, damaged or ill fitting louvre and roller shutter doors, holes where pipes and cables pass through walls, broken airbricks and vents, and open drainage. Older grain stores and barns are the worst offenders because years of settlement and disrepair leave plenty of ground level gaps. They harbour in anything that gives cover: log and pallet piles, old tyres, redundant machinery, overgrown vegetation against walls, and stacked straw or hay.
1. Cut off the food and shelter first. This is the single most effective thing you can do, and baiting works far better once it is done. Clean up feed spillages straight away, store feed in sealed metal bins or secure containers, fix dripping taps and standing water, and clear the clutter rats hide in. Aim to leave an open, tidy strip around buildings, because rats dislike crossing open space and will avoid an exposed approach.
2. Proof the buildings. Once the surroundings are tidy, close the ways in. Fit or repair door sweeps and seals, mesh over vents and louvres with gaps smaller than 10mm, and fill holes around pipework and cabling with wire wool and a suitable filler or cement. Proofing is what stops the next wave, so it is worth doing properly rather than just baiting and hoping.
3. Bait with locked stations, in the right places. Use locked, tamper resistant bait stations and place them where the activity actually is: along walls and runs, near burrow entrances, and around feed stores and building edges, kept in and around buildings rather than scattered across open ground. Rats are naturally wary of new objects, so leaving stations in place for a few days before they are taken is normal, and siting them on established runs improves take. Keep stations against cover and edges, never out in the open where rats will not go and where non target animals are more exposed.
4. Monitor, record and clear up. Check stations regularly, top up where bait is being taken, and keep a simple written record of where you have baited, which product you used and when you checked. Search for and remove dead rats promptly and dispose of them to the product label, because a poisoned rat eaten by a barn owl, buzzard, fox or farm cat passes the poison up the chain. This secondary poisoning risk is exactly why locked stations, correct dosing and carcass removal matter.
Two things are worth knowing before you bait. First, the rules. Farm rodenticides such as bromadiolone and difenacoum now face restrictions on use in open areas under changes that came into effect in 2024, so on a farm they should be used in and around buildings, to the label, rather than broadcast across open land. Permanent or year round baiting is tightly controlled and is not meant as a just in case measure where there are no signs of rats. The Health and Safety Executive oversees this, and following CRRU stewardship guidance is expected, with many farm assurance schemes building it into their standards. You can read the HSE rodenticide guidance for the detail.
Second, resistance. In parts of the UK, particularly the South, rats have developed resistance to some anticoagulant actives, which means a bait that should work can underperform if resistance is present locally. If take is good but the population is not dropping, that is a sign to review the active you are using and the placement rather than simply putting down more of the same. Honesty here saves money, because baiting resistant rats with the wrong active just feeds them.
For a working farm with multiple buildings, the Rat Killer Poison Kit Large gives you eight tamper resistant stations and several bait formats to cover yards, feed stores and outbuildings at once. For a smallholding, a single outbuilding or lighter activity, the Rat Killer Poison Kit Small is usually the better starting point. Both keep bait secure around livestock, pets and children, which matters far more in a farm setting than anywhere else.
Chickens and other poultry are a classic draw, because the feed and the warmth are exactly what rats want, and rats will take eggs and even young birds. Baiting around live poultry needs care, since bait must never be where birds, pets or children can reach it, and a poisoned rat must not be left where a bird could scavenge it. We cover the safe approach in detail in our dedicated guide to rats in chicken coops and poultry houses.
Feed stores are usually where the real damage and contamination happen, and rats foul far more feed than they eat. There is also a legal duty in the background: the Prevention of Damage by Pests Act 1949 places an onus on occupiers of land to keep it reasonably free of rats and mice, and gives local authorities powers to require action. We go into feed protection, disease risk and your duties in our guide to rats, farm feed and the law.
DIY control with locked stations handles most farm rat activity, especially when you act early and proof properly. Bring in a professional where activity is heavy and established across the whole site, where baiting is not reducing numbers (which can point to resistance), where you need permanent baiting that falls under stricter rules, or where a farm assurance scheme requires a documented programme. Note too that some professional rodenticides and larger pack sizes require proof of competence to buy, whereas amateur authorised products like our kits are sold in pack sizes intended for non professional use.
Remove the easy food and shelter first, proof the buildings, then bait with locked stations on the runs rats are actually using. Cutting off food makes the bait far more effective, so doing it in that order clears a colony faster than baiting alone.
In locked tamper resistant stations along walls, runs and burrow entrances and around feed stores and building edges, kept in and around buildings rather than out in open areas. Keep stations against cover, because rats avoid crossing open ground.
Rat numbers build fastest in autumn and winter when field food runs out and rats move toward buildings, and because a breeding pair can become over a thousand rats in a year, a small problem left alone becomes a big one quickly.
Only in locked tamper resistant stations, used strictly to the label, with dead rats removed promptly. That keeps bait away from animals and reduces the risk of a pet or bird being poisoned by eating a dead rat.
No. Rodenticides such as bromadiolone and difenacoum face restrictions on open area use, and open ground baiting exposes non target wildlife. Keep baiting in and around buildings and follow the product label.
If you are seeing rats around your buildings, start by clearing food and shelter and proofing the obvious gaps, then set up locked bait stations on the active runs. For a working farm with several buildings, begin with the Rat Killer Poison Kit Large for the coverage, and for a smallholding or a single building the Rat Killer Poison Kit Small is usually enough. Keep a record of where you bait, check regularly, and clear away any dead rats as you go.
