Puppy potty training regression: why it happens and how to reset

A puppy who was reliably house-trained and is now having accidents again hasn't forgotten everything. Something has changed: more freedom, a different routine, adolescence, stress, a move, a spot that still smells like a toilet, or a health problem such as a urinary infection. Check with your vet first if accidents appear out of the blue, then go back a stage and rebuild. Most setbacks clear up with a few weeks of puppy-level routine.

This page is about the "was trained, now going backwards" case. If your puppy has never been fully reliable, start with our potty training guide and house-training accidents instead.

First, rule out a health problem

When a previously trained dog starts going indoors, the San Francisco SPCA says the first step should always be a visit to your vet, and VCA likewise recommends asking your vet to check for a physical illness, especially when soiling starts suddenly.

The most common culprit to rule out is a urinary tract infection. The AKC lists these signs:

• accidents in the house and needing to go outside more often;
• straining or whimpering while peeing;
• bloody or cloudy urine;
• licking the urinary opening, and sometimes fever.

VCA adds other possibilities, including drinking and peeing more than usual, discomfort when toileting, and digestive problems that change stools. The AKC notes that a dog with a UTI doesn't always show signs, so a vet check is worth it even if you can't spot anything. If you see blood in the urine, the AKC says to contact your vet right away, and if your puppy can't pee at all, that is an emergency.

Too much freedom, too soon

This is the most common non-medical cause. A puppy goes accident-free for a couple of weeks, gets the run of the house, and finds a quiet corner. The AKC says many owners expand access to the home too quickly, and that gradually increasing freedom tends to work better than giving unrestricted access too early. Its article on adolescent puppies calls giving too much freedom too soon a common mistake. The Royal Kennel Club also warns that a back door left open turns the garden into a playground rather than a toilet, so your puppy may stop going out with purpose.

A change in routine or time alone

Puppies toilet on a body clock, so new work hours, a holiday, a missed lunchtime walk or a different feeding time can throw it off. The Royal Kennel Club lists leaving a puppy alone for too long among common mistakes: it may be forced to go indoors and then make a habit of it. Irregular mealtimes and frequent diet changes are on the same list. If the accidents only happen while you're out, see how long a puppy can hold its pee; a house-trained dog that only toilets when left alone may also be struggling with being alone rather than with training.

Adolescence

The AKC says adolescence may begin when a puppy is about eight months old and continue until two years, and that teenage dogs can seem to forget everything they've been taught. Hormones aren't the only factor: a more confident puppy explores further, gets distracted outside and may come back in without having finished. Treat this as a reason to keep the routine up, not to drop it.

Fear, stress and new surroundings

VCA explains that a dog that is frightened outside, or expecting to be, may be too distracted to toilet, and then goes once it's back indoors. Fireworks, building noise or a scary encounter on a walk can all start this. VCA also notes that dogs feeling anxious or frustrated may mark, especially during stressful social situations at home, such as house guests or a new pet.

Moving is a big one. The San Francisco SPCA notes that even dogs who were completely house-trained can forget their training after the upheaval of changing homes. Battersea says dogs who already know house-training usually need about a week to learn the routine in a new home, so expect a short dip and teach the new door and the new toilet spot from scratch.

If the "accidents" are small dribbles only when someone arrives, that's probably not regression at all; read puppy peeing when excited.

Cleaning that leaves a scent behind

VCA says dogs are often attracted to previously soiled spots, and recommends an enzymatic cleaner. Battersea and the Royal Kennel Club both warn against ammonia-based cleaners, which smell similar to urine and can draw a dog back to the same place. One poorly cleaned rug can turn into a repeat toilet. VCA also points out that a dog that had to go indoors while ill can get used to the new spot, so even after a UTI clears up, some retraining may be needed.

The reset plan, step by step

Once your vet has ruled out a medical cause, VCA's advice is to restart as if your dog were a young puppy. In practice:

1. Shrink the world again. Supervise closely whenever your puppy is loose, and confine it when you can't watch, for example in a crate or a puppy-safe area. Our crate training guide covers how. Battersea suggests blocking access to any spot that keeps getting used.
2. Go back to a schedule. Take your puppy out after waking, after meals and after play, and at regular times in between. The potty schedule tool builds a timetable by age, and how often a puppy needs to pee gives the ranges.
3. Go out with your puppy. Use the same spot each time and make sure it actually goes. If it doesn't, VCA suggests bringing it back inside and keeping it in sight until the next try.
4. Reward the moment it finishes outside, with a treat or praise straight away.
5. Interrupt calmly. If you catch your puppy starting to go indoors, VCA suggests a gentle distracting sound and a quick trip outside. Don't frighten or scold.
6. Clean up quietly. Use an enzymatic cleaner, and clean out of your puppy's sight so it doesn't become a game, as Battersea advises.
7. Keep a log. VCA recommends a training journal of pees, poos, diet and health changes, because it can reveal a pattern your vet will want to see.
8. Hand back freedom slowly. Add one room at a time, only after a run of dry days.

When to see the vet

Contact your vet if accidents start suddenly in a puppy that was reliable, if you see any of the UTI signs above, if your puppy is drinking or peeing much more than usual, or if accidents keep happening despite a consistent reset. Battersea lists frequent accidents despite consistent training, sudden incontinence, increased thirst, straining or discomfort as reasons to check with a vet. The AKC advises seeing a vet for persistent house soiling and, once health problems are ruled out, a trainer or behaviourist can help.

For a sense of how long the whole process normally takes, see how long it takes to potty train a puppy.