The cheapest pets by monthly cost are usually small animals like hamsters and rats, costing about $15–$35 per month for food, bedding, and basic care. If you want a longer-term companion, a domestic shorthair cat often provides the best balance of affordability, lifespan, and manageable monthly expenses at around $65–$100 per month.
Last updated: April 27, 2026
- Cheapest monthly pet: Hamsters or rats ($15–$35/month)
- Cheapest low-maintenance pet: Fish ($20–$50/month after setup)
- Best value pet: Domestic shorthair cat ($65–$100/month)
- Cheapest dog: Chihuahua ($85–$125/month)
- Biggest cost drivers: size, food, vet care, grooming, lifespan
Monthly cost is one of the most practical ways to budget for a pet. While lifetime cost matters, most owners experience expenses as recurring monthly spending. This guide breaks down the cheapest pets by monthly cost, including real budget ranges, hidden expenses, and what actually drives ongoing costs.
For broader long-term planning, compare this monthly guide with our cheapest pets to own long-term guide. You can also estimate your own costs with the pet cost calculator. For general pet care cost context, review the ASPCA pet care costs guide and pet ownership data from the AVMA.
Cheapest Pets by Monthly Cost: Quick Comparison
| Rank | Pet | Monthly Cost | Annual Cost | Maintenance | Best For |
|---|---|---|---|---|---|
| 1 | Hamsters or Rats | $15–$35 | $200–$400 | Low | Lowest possible budget |
| 2 | Fish | $20–$50 | $250–$600 | Low–Moderate | Low interaction pets |
| 3 | Domestic Shorthair Cat | $65–$100 | $800–$1,200 | Low | Best long-term value |
| 4 | Chihuahua | $85–$125 | $1,000–$1,500 | Low–Moderate | Cheapest dog breed |
| 5 | Medium Dog | $100–$200 | $1,200–$2,500 | Moderate | Family pets |
Bottom line: Small pets have the lowest monthly costs, but they also offer shorter lifespans. Cats and small dogs cost more each month but provide significantly longer companionship.
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1. Hamsters and Rats: Cheapest Monthly Pets
Hamsters and rats are the most affordable pets on a monthly basis. Their small size keeps food costs low, and their housing requirements are simple compared to larger animals.
Why they are cheap: Minimal food, small living space, inexpensive supplies.
Watch out for: Exotic vet visits can be unexpectedly expensive.
2. Fish: Low Monthly Cost with Higher Setup
Fish are inexpensive to maintain each month, but they require a higher initial investment for tanks, filters, and setup.
Why they are cheap: Fish eat very little, do not need grooming, and usually do not require frequent day-to-day interaction. Once the tank is properly set up, monthly costs often stay low.
Hidden costs: Equipment replacement, water treatment, electricity, filters, tank upgrades, and fish health problems can raise the real cost. A cheap fish can still become expensive if the tank setup is too small, poorly filtered, or difficult to maintain.
Fish are best for owners who want a quiet, low-interaction pet and are comfortable maintaining water quality. They are not always the cheapest pet upfront, but they can be one of the cheapest pets per month after setup.
3. Domestic Shorthair Cat: Best Monthly Value
Cats provide one of the best combinations of affordability and companionship. Monthly costs stay relatively stable and predictable compared to dogs.
Why cats are a strong value: Low grooming needs, moderate food cost, long lifespan.
Hidden costs: Litter, dental care, and senior health issues.
4. Chihuahua: Cheapest Dog Monthly Cost
Chihuahuas are among the cheapest dogs to own monthly due to their small size and low food requirements.
Why they cost less: Chihuahuas eat small portions, need smaller medication doses, use smaller beds and carriers, and usually avoid expensive coat maintenance. Their small size lowers many monthly costs that make larger dogs more expensive.
Hidden costs: Dental care, behavior training, fragile bones, injury risk, and senior care can still raise the total. Small dogs are not automatically cheap if they need frequent vet visits or private training.
Chihuahuas are a good fit for owners who want a dog but need to keep monthly spending controlled. They work especially well for apartment living, but they still need exercise, socialization, and regular preventive care.
5. Medium Dogs: Higher Monthly Costs
Medium-sized dogs cost more monthly because they eat more, require larger supplies, and often need more training, exercise, boarding, or grooming support than small pets.
A medium dog can still be a strong value if adopted from a shelter, especially if vaccines, spay or neuter surgery, and microchipping are included in the adoption fee. Adult mixed-breed dogs may also be easier to budget for because their size, temperament, and care needs are already clearer than a puppy’s.
Why they cost more: More food, larger medication doses, bigger beds and crates, higher boarding costs, and greater training needs.
How to keep costs lower: Choose a healthy adult dog with moderate energy, short coat, predictable temperament, and no known chronic medical issues.
Monthly Pet Cost by Category
| Pet | Food | Vet / Preventive Care | Supplies | Grooming / Maintenance | Total Monthly Estimate |
|---|---|---|---|---|---|
| Hamster or Rat | $5–$10 | $0–$10 saved monthly | $5–$15 | $0–$5 | $15–$35 |
| Fish | $5–$10 | $0–$10 | $5–$20 | $10–$20 | $20–$50 |
| Domestic Shorthair Cat | $25–$50 | $20–$30 saved monthly | $15–$25 | $0–$10 | $65–$100 |
| Chihuahua | $20–$40 | $40–$60 | $10–$20 | $0–$15 | $85–$125 |
| Medium Dog | $40–$80 | $50–$90 | $15–$30 | $0–$50 | $100–$200 |
This table shows why size matters so much. Food, medication, supplies, boarding, and grooming usually rise as pets get larger. Small animals stay cheap because almost every recurring category stays small.
Example Monthly Pet Budget
Here is a realistic example of how monthly pet costs can look for a domestic shorthair cat, one of the best-value pets for long-term companionship.
| Expense | Estimated Monthly Cost | Notes |
|---|---|---|
| Food | $35 | Mid-range dry and wet food mix |
| Litter | $20 | Standard clumping litter |
| Routine vet savings | $25 | Averaged monthly for annual exams, vaccines, and preventive care |
| Toys and supplies | $10 | Replacement toys, scratchers, and small supplies |
| Estimated Total | $90/month | Before emergencies, dental work, or special diets |
This example shows why cats often rank well among the cheapest pets by monthly cost. They cost more than small rodents, but they offer a much longer companionship period and usually remain more affordable than dogs.
Cheapest Pets by Monthly Budget
| Monthly Budget | Best Pet Choices | What to Expect | Watch Out For |
|---|---|---|---|
| Under $50/month | Hamsters, rats, some fish | Lowest ongoing cost, simple supplies, small space needs | Exotic vet care, tank setup, short lifespans |
| $50–$100/month | Domestic shorthair cats, some small pets with better setups | Best balance of affordability and companionship | Litter, dental care, senior health costs |
| $100–$150/month | Chihuahuas, small mixed-breed dogs, cats with higher care needs | Affordable dog ownership becomes realistic | Training, preventives, dental care, pet sitting |
| $150–$250/month | Medium dogs, active family dogs, multi-pet homes | More flexibility for food, care, and supplies | Boarding, grooming, emergencies, behavior support |
If your budget is under $50 per month, small animals are usually the safest choice. If you can spend closer to $100 per month, a domestic shorthair cat becomes one of the best value pets. Dog ownership usually becomes more realistic once your budget reaches at least $100–$150 per month.
Monthly Cost vs Lifetime Cost: Which Matters More?
Monthly cost helps you decide whether a pet fits your current budget. Lifetime cost helps you understand the full financial commitment. You need both numbers before choosing a pet.
| Cost Type | What It Tells You | Best Use |
|---|---|---|
| Monthly Cost | How much you may spend every month | Budgeting for food, litter, supplies, and routine care |
| Annual Cost | How much the pet may cost each year | Planning recurring care and savings |
| Lifetime Cost | Total ownership cost over the pet’s life | Comparing long-term financial commitment |
A hamster may be the cheapest pet per month and lifetime, but it also has a short lifespan. A cat costs more monthly but can be a better long-term value because it may live 15–20 years. For a full lifetime view, compare this guide with our cheapest pets to own long-term breakdown.
What Drives Monthly Pet Costs?
- Food: The biggest recurring expense, especially for larger pets
- Vet care: Routine checkups, vaccines, and preventive treatments
- Supplies: Bedding, litter, toys, and replacements
- Grooming: Varies widely depending on breed
- Size: Larger pets increase almost every cost category
Hidden Monthly Costs
The cheapest pets by monthly cost can still become expensive if you only budget for food. Emergency care, dental work, equipment replacement, and travel care often surprise new owners.
- Emergency vet visits: Accidents, injuries, illness, and poisoning can cost far more than routine monthly care.
- Medication or chronic illness: Senior pets and pets with ongoing conditions may need regular prescriptions or special diets.
- Boarding or pet sitting: Travel can add recurring costs for cats and dogs.
- Training and behavior support: Dogs may need classes or private training, especially if adopted with unknown history.
- Dental care: Cats and small dogs often need dental cleanings as they age.
- Equipment replacement: Fish tanks, filters, cages, carriers, beds, scratchers, and toys all wear out over time.
Compare monthly and lifetime costs side by side
Use the calculator to estimate real costs before choosing a pet.
FAQ
What is the cheapest pet by monthly cost?
Hamsters and rats are usually the cheapest pets by monthly cost, typically costing about $15–$35 per month for food, bedding, and basic supplies.
What pet costs under $50 per month?
Hamsters, rats, and some fish can cost under $50 per month after setup. Owners should still budget for occasional vet care, equipment replacement, or supply upgrades.
Are cats cheaper than dogs per month?
Yes. Cats are usually cheaper than dogs per month because they often need less food, less grooming, and fewer routine service costs. A domestic shorthair cat may cost about $65–$100 per month.
What is the cheapest dog by monthly cost?
Chihuahuas are often one of the cheapest dogs by monthly cost because they eat very little, need smaller supplies, and usually require minimal grooming.
Are fish cheaper than cats per month?
Fish can be cheaper than cats per month after setup, but tanks, filters, water treatment, and equipment replacement can make upfront and maintenance costs higher than expected.
How much should I budget monthly for a pet?
Small pets may cost $15–$50 per month, cats often cost $65–$100 per month, and dogs commonly cost $85–$200 or more depending on size, grooming, health, and location.
Why do larger pets cost more each month?
Larger pets usually cost more because they eat more, need larger supplies, require higher medication doses, and often have higher grooming, boarding, and veterinary expenses.
How can I reduce monthly pet costs?
You can reduce monthly pet costs by choosing a smaller pet, adopting instead of buying, keeping up with preventive care, avoiding high-grooming breeds, and setting aside money for emergencies.
The cheapest pets by monthly cost are small animals like hamsters and rats. Cats offer the best long-term value, while small dogs like Chihuahuas remain the most affordable dog option for ongoing expenses.
For a detailed breakdown of how these costs are calculated, see our pet cost methodology page.