I own both, so I can tell you from direct experience: the idea that cats are basically free compared to dogs is a myth. Cats are cheaper, yes. But "cheaper" and "cheap" are different words, and the gap isn't as dramatic as people assume once you account for everything.
Here's the honest comparison, category by category, based on typical annual costs for a healthy adult pet. I'm using ranges because costs vary hugely depending on where you live, the size of your dog, and your standards for things like food quality and veterinary care.
Food
This is where the biggest gap lives.
Dogs: $300 to $1,000+ per year. A 50-pound dog eating a mid-range kibble goes through a lot of food. Large and giant breeds can push food costs well over $1,000 annually, especially if you're feeding a higher-quality diet or supplementing with wet food.
Cats: $200 to $600 per year. Cats just eat less. An average adult cat consumes roughly 200 to 300 calories per day. Even with a quality wet-and-dry combination, you're buying less product.
Winner: Cats, by a significant margin. And it only gets more dramatic with larger dogs.
Veterinary Care
Routine vet costs are closer than most people think.
Dogs: $200 to $500+ per year for annual exams, vaccinations, and preventatives (flea/tick and heartworm medication). Heartworm prevention alone adds $50 to $200 per year, and it's not optional in many regions.
Cats: $150 to $400 per year for annual exams, vaccinations, and flea prevention. Indoor cats need fewer preventatives than dogs, which brings the baseline down.
Winner: Cats, but the margin is smaller than the food category. And one unexpected illness evens the playing field fast — emergency vet costs don't discriminate by species.
Grooming
This is the category where the difference is either nonexistent or enormous, depending entirely on the dog.
Dogs: $0 to $800+ per year. Short-haired, low-maintenance breeds might need nothing beyond the occasional bath. Dogs with long, curly, or double coats can need professional grooming every 4 to 8 weeks, and each session runs $40 to $100+.
Cats: Most cats handle their own grooming. Long-haired cats may benefit from occasional professional grooming ($50 to $100 per session), but most cat owners spend close to $0 on this.
Winner: Cats, decisively — unless you happen to have a short-haired dog and a Persian cat, in which case, life is unpredictable.
Litter vs. Outdoor Costs
Here's where cats have an expense dogs don't.
Cats: $150 to $400 per year on litter. This is ongoing, unavoidable, and surprisingly expensive over time. Multi-cat households multiply this number.
Dogs: $0 for litter, but you might spend $50 to $200 per year on waste bags, and there's an indirect cost in time — somebody has to walk the dog for bathroom breaks, and in rough weather, that somebody would rather be on the couch.
Winner: Dogs, technically. But it's one of the few categories where they come out ahead.
Training
Dogs: $100 to $500+ in the first year for basic obedience classes, and potentially ongoing costs for behavioral training. Even well-behaved dogs benefit from training, and some breeds need more than others.
Cats: Basically $0. Cats don't go to obedience school. You might spend a few dollars on treats for litter box training or enrichment, but formal training isn't a line item in the cat budget.
Winner: Cats. This one isn't close.
Boarding and Pet Sitting
Dogs: $200 to $1,500+ per year if you travel. Dog boarding typically runs $30 to $85 per night, and dog walking services add up if you use them regularly. Daycare — if your dog benefits from the socialization — can run $20 to $50 per day.
Cats: $100 to $500+ per year. Cat sitting is generally less expensive than dog boarding because cats need less active care. Many cat owners arrange for a neighbor or friend to visit once or twice daily, which can cost nothing or a modest fee.
Winner: Cats. Dogs need more active care when you're away, and the costs reflect that.
The Real Totals
Adding it all up for a healthy adult year:
Dogs: $1,000 to $3,000+ (small breeds on the low end, large breeds on the high end, high-maintenance breeds potentially higher)
Cats: $500 to $1,500 (with most indoor cats landing in the $700 to $1,200 range)
On average, dogs cost roughly 1.5 to 2 times as much as cats annually. But averages hide a lot of individual variation. A low-maintenance mutt might cost less per year than a cat with a chronic urinary condition. A healthy tabby costs a fraction of what a standard poodle does in grooming alone.
For a full year-by-year breakdown of pet ownership costs, including how expenses shift as pets age, I've covered that in detail. And if you're specifically wondering about startup costs, I've also looked at first-year costs for puppies specifically and first-year costs for kittens specifically.
The Categories That Even the Score
Two things narrow the cat-vs-dog cost gap more than people expect:
Senior health care. Cats live longer than most dogs, and those extra years come with extra costs. Chronic kidney disease is common in older cats and can mean monthly vet visits, prescription food, and medications. A senior cat's annual costs can rival or exceed a healthy adult dog's.
The stuff you buy because you feel guilty. This isn't in any budget spreadsheet, but it's real. Cat trees, new toys because the old ones got boring, the fancy food topper, the heated bed. Dog owners spend more on impulse items in total, but cat owners aren't immune — and the "treats and extras" category is where budgets quietly fall apart for both species.
FAQ
Does dog size affect the cost comparison?
Massively. A Chihuahua eating a cup of food per day costs a fraction of what a Great Dane costs in food alone. When you factor in higher grooming costs, larger doses of flea/tick medication, bigger crates, and potentially higher boarding fees for large dogs, the gap between dogs and cats widens considerably as dog size increases.
Are there any categories where dogs are cheaper than cats?
Litter is the main one. Dogs don't need it, and that's a real savings of $150 to $400+ per year. Dogs also don't need scratching posts replaced regularly. Beyond that, dogs tend to cost the same or more in almost every category.
Does the cost difference matter over a lifetime?
Yes — it compounds. Over a 12-year span, the annual difference of $500 to $1,500 per year adds up to $6,000 to $18,000 in total savings for cat ownership. That's a real number. But it shouldn't be the deciding factor — the right pet for your life isn't always the cheapest one.
What if I have both a dog and a cat?
Some costs overlap or get shared — you're already going to the vet, you already have basic supplies. But most expenses are simply additive. Food, litter, preventatives, and boarding costs don't drop because you have multiple species. The combined total is usually close to the sum of individual costs, though bulk buying food and scheduling vet visits together can save small amounts.