Common Causes (Ranked by Likelihood)
Feline UTIs cause cats to urinate more frequently, sometimes in unusual locations, and to lick the urogenital area excessively — spreading urine smell across their coat. The urine itself from a UTI-affected cat is often more pungent than normal, due to bacterial activity producing additional odorous compounds. Female cats are more susceptible to UTIs than males. UTIs can progress to bladder infections and kidney involvement if untreated. Cats may also develop feline idiopathic cystitis (FIC) — similar symptoms without infection.
Many cats — especially long-haired breeds, cats with mobility issues, or cats who scratch enthusiastically in the litter box — get urine on their fur during elimination. The paws, belly, and hindquarters are most commonly affected. A litter box that's too small forces cats to stand in or near urine. Clumping litter stuck to paws spreads urine-soaked material throughout the house and onto the cat's coat. This is the most common cause of a 'urine smell' cat that has no underlying medical issue.
Chronic kidney disease (CKD) is extremely common in older cats — about 30-40% of cats over 10 years old are affected. As kidneys fail, they lose the ability to concentrate urine, so cats produce large volumes of very dilute urine (and drink more water to compensate). More critically, impaired kidneys allow urea to accumulate in the blood (uremia), which is then excreted through skin, breath, and saliva — creating a persistent urine or ammonia smell on the cat's coat. This is distinct from urine contamination: the smell comes from the cat's skin itself.
Feline diabetes causes high blood glucose, which spills into the urine — creating sweet-smelling urine in mild cases, but also causing increased urination that can result in urine contact with the coat. Diabetic cats also break down fat and protein for energy, producing ketones and urea that are excreted through skin and breath. Uncontrolled diabetes can produce a urine-like or fruity/sweet odor from the cat's body. Risk factors include obesity, male sex, and age.
Cats are meticulous self-groomers, but this declines with age due to arthritis (making it painful to reach the hindquarters), dental disease, obesity, or cognitive decline. When a cat stops grooming effectively, urine residue from normal urination accumulates on the fur — especially around the tail base and hindquarters — producing persistent urine odor. This isn't a disease itself but is often a sign that something else (arthritis, dental pain, obesity) needs addressing.
How to Fix It
Get a Vet Checkup for Medical Causes
$75-400Essential first step for cats with persistent urine odor — especially older cats.
- 1Book a vet visit. A urinalysis ($50-100) can diagnose UTI, kidney disease, and diabetes in one test.
- 2For senior cats, ask for a senior bloodwork panel — this checks kidney values (BUN, creatinine), blood glucose, and other markers.
- 3UTIs are treated with antibiotics (typically a 7-14 day course, $50-150 total).
- 4Early CKD is managed with a kidney-specific diet, increased water intake, and sometimes medication — cats can live well for years with managed CKD.
- 5Diabetes is treated with insulin injections and dietary change — manageable at home with proper training.
Address Litter Box Hygiene and Setup
$0-50For cats whose urine smell is from litter contamination rather than medical cause.
- 1Upgrade to a larger litter box — the rule is box length should be 1.5x the cat's body length. Most commercial boxes are too small.
- 2Scoop twice daily and do a full litter change every 1-2 weeks.
- 3Try a high-sided or covered box to reduce splatter on walls and the cat.
- 4Wipe the cat's paws and hindquarters with unscented pet wipes after litter box visits if they're consistently contaminating their fur.
- 5For long-haired cats, trim the fur around the hindquarters (the 'sanitary clip') to reduce urine absorption.
Bathe or Spot-Clean the Cat
$5-30For immediate odor removal while addressing the underlying cause.
- 1Use an enzymatic pet shampoo specifically designed to break down urine compounds. Regular cat shampoo only masks the smell temporarily.
- 2For cats that won't tolerate baths, enzymatic waterless spray or pet wipes applied to the affected area work well.
- 3Focus on the hindquarters, belly, and paws where contamination concentrates.
- 4Dry thoroughly after bathing — damp fur can develop its own odors.
- 5For older cats with mobility issues, regular gentle grooming with a brush and periodic spot cleaning may be needed as a management strategy.
When to Call a Professional
Male cat straining to urinate with little or no output — this is a urinary blockage and is a life-threatening emergency. Go to an emergency vet immediately.
Urine smell with dramatic weight loss, lethargy, or vomiting — kidney disease or diabetes in a serious state; vet visit within 24 hours.
Blood visible in urine — requires vet evaluation promptly.
Cat with urine smell stops eating or drinking for more than 24 hours — potentially very serious regardless of cause.
Urine smell from a cat that was previously odorless — any sudden change in body odor warrants investigation.
How to Prevent It
Annual vet checkups — blood and urine testing catches kidney disease and diabetes early, before they become serious.
Senior cats (8+) should have twice-yearly bloodwork — kidney disease in cats progresses silently.
Keep litter boxes large, clean, and numerous (one per cat plus one) to minimize fur contamination.
Maintain a healthy weight in your cat — obesity is a major risk factor for feline diabetes.
Encourage water intake — feed wet food and use a cat water fountain, which increases drinking and supports kidney health.
Regular grooming, especially for long-haired breeds — reduces urine accumulation in fur.
Why Cat Urine Smells So Strongly
Cat urine is chemically distinct from human or dog urine — it contains high concentrations of urea, urobilin (which gives it the yellow color and characteristic smell), creatinine, and a compound called felinine that's unique to cats. Felinine is a sulfur-containing amino acid found almost exclusively in cat urine, where it's broken down by bacteria into volatile sulfur compounds (including 3-mercapto-3-methylbutan-1-ol) that have an extremely intense, persistent smell.
Male cats produce more felinine than females, which is why intact male cat urine is dramatically more pungent — testosterone drives felinine production. Neutering significantly reduces felinine levels and the associated odor. This is one of the most impactful reasons to neuter male cats early.
When a cat smells like urine from its coat rather than from a nearby soiled area, it means either urine is physically on the fur (grooming issue, litter contamination) or these compounds are being excreted through the skin (kidney disease, uremia). The distinction matters for treatment — one is a hygiene fix, the other requires medical management.
Frequently Asked Questions
Sudden onset urine odor in a cat most commonly means a UTI, especially in younger cats. In older cats, it can signal the onset of kidney disease or diabetes. It can also be as simple as the cat sitting in urine in the litter box. If the smell doesn't resolve after a bath and litter box improvement, a vet visit is warranted — sudden odor changes in cats are usually medically significant.
If the litter box is clean but the cat still smells, the urine is coming from the cat itself rather than the environment. This points to medical causes: UTI (urine on fur from excessive licking), kidney disease (urea excreted through skin), or diabetes. A vet urinalysis and bloodwork will usually identify the cause.
Senior cats smell like urine for three main reasons: kidney disease (very common in cats over 10, urea is excreted through skin), diabetes (similar mechanism), or reduced grooming due to arthritis or dental pain that lets urine accumulate in the coat. Senior bloodwork including kidney values and blood glucose is the right starting point.
Diet doesn't typically cause a cat to smell like urine from its coat. However, very high protein diets increase urea production, and raw diets with fish can produce stronger-smelling urine. The urine odor coming from the cat's body (rather than wet spots) is almost always a health or grooming issue rather than diet.