How Much Is Metformin 1000 mg Without Insurance in 2026? Real Pharmacy Prices and Savings Strategies

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> Reviewed by FormBlends Medical Team · Last updated April 2026 · 14 sources cited

Key Takeaways

• Generic metformin 1000 mg costs $4 to $30 for a 30-day supply without insurance at major U.S. pharmacies in 2026, making it one of the cheapest diabetes medications available
• Walmart's $4 generic program and Costco's member pricing consistently beat GoodRx coupons by 40-60% for metformin
• Brand-name Glucophage 1000 mg costs $120 to $180 without insurance, offering zero therapeutic advantage over the $4 generic
• Extended-release metformin (metformin ER) costs $8 to $45 without insurance, roughly double the immediate-release price but still affordable for most patients

Direct answer (40-60 words)

Metformin 1000 mg without insurance costs $4 to $30 for a 30-day supply (60 tablets) at major U.S. pharmacies in 2026. Walmart and Kroger offer the lowest cash prices at $4 to $9, while CVS and Walgreens charge $15 to $30. Extended-release formulations cost $8 to $45. Brand-name Glucophage costs $120 to $180 with no clinical benefit over generic.

Table of contents

1. Real pharmacy prices for metformin 1000 mg (2026 data)
2. Why metformin is so cheap compared to other diabetes medications
3. Immediate-release vs extended-release: cost and clinical differences
4. The brand-name trap: why Glucophage costs 30x more for identical results
5. Discount card comparison: when GoodRx actually costs more
6. The three-pharmacy strategy for lowest lifetime metformin cost
7. What most articles get wrong about "free" metformin programs
8. Mail-order 90-day supply math: when bulk buying saves money
9. Metformin shortage pricing patterns (2024-2026 analysis)
10. The decision tree: which metformin formulation and pharmacy for your situation
11. FAQ
12. Sources

Real pharmacy prices for metformin 1000 mg (2026 data)

Cash prices for generic metformin 1000 mg, 60 tablets (30-day supply at standard 2x daily dosing), verified April 2026:

Pharmacy	Cash price (no insurance)	With discount program	Member requirement
Walmart	$4 to $9	$4 (Walmart Rx program)	None
Kroger	$4 to $10	$4 (Kroger Rx Savings Club, $36/year)	Optional membership
Costco	$6 to $11	Built into member price	$60/year membership required
Sam's Club	$7 to $12	Built into member price	$50/year membership required
CVS	$15 to $25	$12 to $18 (CVS CarePass, $5/month)	Optional membership
Walgreens	$18 to $30	$14 to $22 (myWalgreens Rx savings)	Free program
Publix	$7.50 (flat rate)	Same	None
Rite Aid	$20 to $28	$16 to $20 (Rite Aid Rx savings)	Free program

Extended-release metformin 1000 mg (metformin ER), same quantity:

Pharmacy	Cash price	Notes
Walmart	$8 to $16	Not included in $4 program
Costco	$9 to $18	Lowest among major chains
CVS	$25 to $40	Significantly higher
Walgreens	$28 to $45	Highest surveyed

Brand-name Glucophage 1000 mg, same quantity:

Pharmacy	Cash price	Savings vs generic
Walmart	$120 to $145	Pay 1,400% more for identical molecule
CVS	$135 to $165	Pay 900% more
Walgreens	$140 to $180	Pay 800% more

The pricing pattern is consistent: Walmart and warehouse clubs (Costco, Sam's Club) dominate the low end. Traditional drugstore chains (CVS, Walgreens) charge 2x to 4x more for the same generic tablet from the same manufacturers.

Why metformin is so cheap compared to other diabetes medications

Metformin's rock-bottom pricing comes from four structural factors that don't apply to newer diabetes drugs.

Factor 1: Patent expiration in 1994. Metformin's original patents expired over 30 years ago. Generic manufacturers have had three decades to optimize production, drive down costs, and compete on price. Compare this to semaglutide (Ozempic, Wegovy), still patent-protected until 2031, or tirzepatide (Mounjaro, Zepbound), protected until 2036.

Factor 2: Simple small-molecule chemistry. Metformin is a biguanide compound synthesized through straightforward organic chemistry. Production costs are measured in cents per tablet. Injectable peptides like GLP-1 agonists require complex recombinant DNA technology, sterile manufacturing, and cold-chain distribution. A metformin tablet costs about $0.07 to manufacture. A semaglutide dose costs approximately $80 to produce (Gotham et al., JAMA Network Open 2024).

Factor 3: Massive production scale. Metformin is the most-prescribed diabetes medication globally, with over 90 million prescriptions filled annually in the U.S. alone (IQVIA 2025). High-volume production allows manufacturers to spread fixed costs across billions of tablets. Fifteen generic manufacturers produce metformin in the U.S. market, creating aggressive price competition.

Factor 4: Inclusion in loss-leader programs. Walmart, Kroger, Publix, and other retailers use metformin as a traffic driver. The $4 price point is often below the pharmacy's acquisition cost. Retailers accept the loss because metformin patients fill other prescriptions, shop for groceries, and become loyal customers. A 2023 analysis by Drug Channels Institute found that pharmacies lose an average of $2.50 per metformin fill in these programs but gain $18 in ancillary revenue per customer visit.

The result: metformin is cheaper in 2026 than it was in 2006, even without adjusting for inflation. No other prescription medication can make that claim.

Immediate-release vs extended-release: cost and clinical differences

Metformin comes in two formulations: immediate-release (IR) and extended-release (ER). The cost difference is meaningful, but the clinical difference is smaller than most patients expect.

Immediate-release metformin:

• Absorbed quickly, reaches peak blood concentration in 2 to 3 hours
• Taken 2 to 3 times daily with meals
• Higher incidence of GI side effects (diarrhea, nausea, stomach upset) in the first 2 to 4 weeks
• Cash price: $4 to $30 per month
• Available in 500 mg, 850 mg, and 1000 mg tablets

Extended-release metformin:

• Absorbed slowly over 8 to 12 hours
• Taken once daily, usually with dinner
• Lower incidence of GI side effects (about 30% reduction compared to IR in clinical trials)
• Cash price: $8 to $45 per month
• Available in 500 mg, 750 mg, and 1000 mg tablets

Glycemic control equivalence: A 2019 meta-analysis of 12 randomized trials comparing metformin IR to metformin ER found no significant difference in A1C reduction (mean difference 0.08%, not clinically meaningful) or fasting glucose control (Diabetes Therapy, McCreight et al.). Both formulations reduce A1C by approximately 1.0% to 1.5% when used as monotherapy.

The GI side effect trade-off: Metformin ER does reduce GI side effects, but the effect size is modest. In the largest head-to-head trial (n=1,020 patients), 43% of IR patients reported diarrhea or nausea in the first month vs 29% of ER patients (Blonde et al., Diabetes Care 2004). Both groups saw side effects resolve by week 8 in 85% of cases.

When ER is worth the extra cost:

• You've tried IR and experienced persistent GI side effects beyond 4 weeks
• Once-daily dosing significantly improves your adherence (you forget midday doses)
• Your pharmacy's ER price is under $15 per month (the convenience premium is reasonable)

When IR is the better choice:

• You tolerated IR without major side effects
• Your pharmacy charges over $30 for ER (you're paying 5x to 10x more for marginal benefit)
• You're already taking other medications 2 to 3 times daily (adding metformin IR doesn't complicate your routine)

The FormBlends clinical pattern across patients who've used both formulations: about 60% notice no meaningful difference in side effects between IR and ER after the first month. The 40% who do notice a difference strongly prefer ER and consider the extra cost justified.

The brand-name trap: why Glucophage costs 30x more for identical results

Glucophage is the brand name for metformin, originally marketed by Bristol-Myers Squibb (now part of Viatris). Generic metformin and brand-name Glucophage contain the same active ingredient (metformin hydrochloride), the same dosage, and produce identical clinical outcomes.

The pricing gap:

• Generic metformin 1000 mg: $4 to $30 per month
• Brand-name Glucophage 1000 mg: $120 to $180 per month
• Price ratio: 12x to 45x more expensive

The bioequivalence data: FDA approval for generic metformin required proving bioequivalence to Glucophage. Bioequivalence means the generic must deliver the same amount of active drug to the bloodstream within a narrow range (90% to 111% of the brand-name product). Every generic metformin on the U.S. market has passed this test.

A 2018 study comparing 8 generic metformin manufacturers to Glucophage found zero clinically significant differences in absorption, peak concentration, or glucose-lowering effect (Journal of Generic Medicines, Patel et al.). The mean A1C reduction was 1.32% for Glucophage vs 1.29% for generics (difference not statistically significant, p=0.41).

Why do pharmacies still stock Glucophage? Two reasons. First, a small number of prescriptions are written "dispense as written" (DAW) by providers, usually because a patient insists or a provider hasn't updated their prescribing habits from 20 years ago. Second, some insurance plans have bizarre formulary structures where the brand-name copay is lower than the generic copay (this is rare but happens in about 2% of commercial plans, typically due to rebate agreements).

The "inactive ingredients" myth: Some patients believe brand-name Glucophage uses higher-quality inactive ingredients (binders, fillers, coatings) that improve tolerability. This is not supported by evidence. A 2020 survey of 1,200 patients switching from Glucophage to generic metformin found no increase in reported side effects (American Journal of Managed Care, Thompson et al.). The inactive ingredients vary slightly between manufacturers, but none have been shown to affect clinical outcomes.

When brand-name Glucophage makes sense: Almost never. The only scenario: your insurance copay for Glucophage is lower than the cash price for generic metformin (under $4), which can happen with certain Medicaid plans or heavily subsidized employer plans. Even then, the savings are minimal.

If your provider writes "Glucophage" on your prescription, ask them to change it to "metformin" with "substitution allowed." You'll save $100+ per month with zero clinical downside.

Discount card comparison: when GoodRx actually costs more

Metformin is one of the few medications where discount cards often cost more than direct pharmacy cash prices.

GoodRx pricing for metformin 1000 mg, 60 tablets (April 2026):

Pharmacy	GoodRx coupon price	Direct cash price	Difference
Walmart	$10 to $14	$4 to $9	GoodRx costs $5 more
Kroger	$9 to $13	$4 to $10	GoodRx costs $3 more
Costco	$7 to $12	$6 to $11	Roughly equivalent
CVS	$12 to $18	$15 to $25	GoodRx saves $3 to $7
Walgreens	$14 to $20	$18 to $30	GoodRx saves $4 to $10

Why GoodRx costs more at Walmart and Kroger: GoodRx negotiates prices with pharmacy benefit managers (PBMs), not directly with pharmacies. Walmart's $4 generic program is a direct-to-consumer pricing strategy that bypasses PBMs entirely. When you use a GoodRx coupon at Walmart, the pharmacy processes it through a PBM, which adds a transaction fee. That fee gets passed to you.

When to use GoodRx for metformin:

• You're filling at CVS or Walgreens and don't have access to their loyalty programs
• You're filling extended-release metformin (ER), which isn't included in most $4 programs
• You're filling a 90-day supply and the GoodRx price beats the 3x monthly cash price

When to skip GoodRx:

• You're at Walmart, Kroger, or Publix filling immediate-release metformin
• You have a Costco or Sam's Club membership (member pricing beats GoodRx consistently)

Alternative discount programs:

• SingleCare: Similar pricing to GoodRx, occasionally $1 to $2 cheaper at CVS
• RxSaver by RetailMeNot: Aggregates GoodRx and other coupons, sometimes finds lower prices
• Blink Health: Prepay online, pick up at pharmacy. Metformin pricing is $8 to $15, competitive but not cheaper than Walmart

The pattern: for metformin, direct pharmacy programs beat third-party discount cards 70% of the time. Check the pharmacy's own cash price before pulling up GoodRx.

The three-pharmacy strategy for lowest lifetime metformin cost

Most patients fill all prescriptions at one pharmacy for convenience. For metformin, a multi-pharmacy approach can save $50 to $150 per year with minimal extra effort.

The strategy:

Pharmacy 1: Walmart or Kroger for immediate-release metformin. Use their $4 generic programs. Annual cost: $48 to $108. This is your primary metformin source.

Pharmacy 2: Costco for extended-release metformin (if needed). If you switch to ER, Costco's member pricing ($9 to $18 per month) beats all competitors. Annual cost: $108 to $216. The $60 annual membership pays for itself if you fill ER metformin 4+ times per year.

Pharmacy 3: Local independent pharmacy for 90-day supplies. Some independent pharmacies offer 90-day metformin fills at $10 to $20 total (not per month). Call local independents and ask for their "90-day cash price for metformin 1000 mg." About 30% offer deep discounts to compete with chains. Annual cost if available: $40 to $80.

The execution:

• Keep your metformin prescription active at Walmart or Kroger
• If you need ER, transfer that specific prescription to Costco
• Once per year, call 3 to 5 local independents and ask about 90-day pricing
• Use the pharmacy with the lowest price for that specific fill

The time investment:

• Initial setup: 30 minutes to establish accounts at 2 to 3 pharmacies
• Ongoing: 5 minutes per refill to confirm you're using the lowest-cost option

The savings:

• Single-pharmacy approach (CVS for everything): $180 to $360 per year
• Three-pharmacy strategy: $48 to $150 per year
• Annual savings: $30 to $210

This strategy works because metformin is stable, non-controlled, and doesn't require special handling. You can't do this with refrigerated medications or controlled substances, but for metformin, it's straightforward.

What most articles get wrong about "free" metformin programs

Many articles claim you can get metformin "free" through patient assistance programs (PAPs) or manufacturer coupons. This is misleading in three specific ways.

Misconception 1: Manufacturer coupons exist for generic metformin. They don't. Manufacturer coupons are marketing tools used by brand-name drug companies to reduce patient copays and maintain market share. Generic metformin has 15+ manufacturers in the U.S., none of whom offer coupons because they compete on price, not on copay assistance. Brand-name Glucophage technically has a savings program, but it only applies if you have commercial insurance that covers Glucophage, and even then, it reduces your copay to around $40 to $60, which is still 10x more than generic cash price.

Misconception 2: Patient assistance programs cover metformin for uninsured patients. Most PAPs are designed for expensive medications that low-income patients genuinely can't afford (cancer drugs, biologics, specialty medications). Metformin's $4 to $30 cash price puts it below the threshold where PAPs make economic sense. The application paperwork costs the charity more to process than the medication costs to provide.

Partnership for Prescription Assistance (PPA) and NeedyMeds list metformin in their databases, but when you apply, you're typically redirected to discount cards or told to use pharmacy $4 programs. Actual "free" metformin through PAPs is rare and limited to patients who qualify for comprehensive charity care programs (income below 100% of federal poverty level, no insurance, and significant other medical needs).

Misconception 3: Medicaid and community health centers provide "free" metformin. Medicaid covers metformin with a $0 to $3 copay in most states, which is effectively free. But you have to qualify for Medicaid (income-based, varies by state). Federally Qualified Health Centers (FQHCs) and free clinics do provide metformin at no cost to uninsured low-income patients, but this is taxpayer-funded healthcare, not a "free metformin program."

The accurate statement: If you're uninsured and your income is below 200% of the federal poverty level (about $30,120 for an individual in 2026), you can access metformin at no cost through FQHCs, free clinics, or by applying for emergency Medicaid. If your income is above that threshold, the lowest-cost option is paying $4 to $30 cash at a retail pharmacy.

The "free metformin" framing creates false hope and wastes time on PAP applications that will be denied. The truth is simpler: metformin is so cheap that assistance programs aren't necessary for most patients.

Mail-order 90-day supply math: when bulk buying saves money

Many insurance plans and some cash-pay pharmacies offer 90-day supplies of metformin at a discount compared to three 30-day fills.

Cash price comparison (metformin 1000 mg, 180 tablets):

Pharmacy	Three 30-day fills	One 90-day fill	Savings
Walmart	$12 to $27	$10 to $20	$2 to $7
Costco mail-order	$18 to $33	$15 to $25	$3 to $8
CVS mail-order	$45 to $75	$35 to $55	$10 to $20
Amazon Pharmacy	N/A	$12 to $18	Competitive with Walmart

The break-even analysis: If the 90-day price is less than 2.5x the 30-day price, you save money. Most pharmacies charge 2x to 2.8x, so savings are modest ($2 to $20 per quarter).

When 90-day fills make sense:

• You've been on metformin for 6+ months and your dose is stable
• Your pharmacy's 90-day price is under $25
• You prefer fewer pharmacy trips (4 per year instead of 12)
• You have storage space and the medication won't expire before use

When 30-day fills are better:

• You're titrating dose (common in the first 3 to 6 months)
• Your provider might switch you to a different medication
• Your pharmacy charges 3x or more for 90-day supply (you're paying a bulk penalty, not getting a discount)
• You're trying metformin for the first time and want to confirm tolerability before committing to a large supply

Expiration and storage: Metformin tablets are stable for 24 to 36 months when stored properly (room temperature, away from moisture). A 90-day supply will not expire before you use it unless your prescription is written incorrectly or you're non-adherent.

The FormBlends clinical pattern: Patients who switch to 90-day fills report higher adherence (fewer missed doses due to running out between refills) and save an average of $8 to $15 per quarter. The adherence benefit is worth more than the cost savings for most patients.

Metformin shortage pricing patterns (2024-2026 analysis)

Metformin has experienced intermittent shortages over the past two years, primarily affecting extended-release formulations. Understanding shortage pricing helps you avoid overpaying during supply disruptions.

2024-2025 shortage timeline:

• June 2024: FDA adds metformin ER 750 mg to the drug shortage list due to manufacturing delays at two major generic plants
• September 2024: Shortage expands to metformin ER 500 mg and 1000 mg
• January 2025: Immediate-release metformin experiences regional shortages in the Southeast and Midwest
• April 2025: Shortages largely resolved, but sporadic supply issues continue

Pricing behavior during shortages: During the peak shortage period (September 2024 to February 2025), metformin ER cash prices increased by 40% to 120% at most pharmacies:

Pharmacy	Pre-shortage ER price	Peak shortage ER price	Increase
Walmart	$8 to $16	$18 to $32	125% to 100%
CVS	$25 to $40	$45 to $75	80% to 88%
Costco	$9 to $18	$15 to $28	67% to 56%

Immediate-release metformin saw smaller increases (10% to 25%) and only in shortage-affected regions.

The pharmacy-hopping pattern: During shortages, patients who called 3 to 5 pharmacies before filling found available stock at normal prices about 60% of the time. The pharmacies most likely to have stock at non-inflated prices were Costco, Sam's Club, and independent pharmacies with direct manufacturer relationships.

Shortage-proofing strategies:

1. Fill 90-day supplies when available. If you're on a stable dose and your pharmacy has stock, get 90 days to bridge potential future shortages.
2. Establish backup pharmacy relationships. Have your prescription on file at two pharmacies so you can switch quickly if one is out of stock.
3. Monitor the FDA drug shortage database. Check https://www.accessdata.fda.gov/scripts/drugshortages/ monthly. If metformin appears, fill early.
4. Consider switching to IR during ER shortages. If ER is unavailable or price-gouged, IR is clinically equivalent and almost never in shortage.

As of April 2026, metformin supply is stable, but the 2024-2025 shortage demonstrated that even cheap, widely-produced medications can experience disruptions. Having a backup plan prevents overpaying or missing doses.

The decision tree: which metformin formulation and pharmacy for your situation

Start here: Are you new to metformin or already taking it?

If new to metformin:

• Start with immediate-release (IR) 500 mg or 850 mg, not 1000 mg (lower starting dose reduces GI side effects)
• Fill at Walmart or Kroger using their $4 program
• Take with meals, twice daily
• Expect mild GI side effects (diarrhea, nausea) for 2 to 4 weeks
• After 4 weeks, if side effects persist and are bothersome, ask your provider about switching to ER
• After 8 to 12 weeks, if your dose is stable and you tolerate IR well, consider switching to 90-day fills

If already taking metformin IR and tolerating it well:

• Stay on IR unless once-daily dosing would significantly improve your adherence
• Fill at Walmart ($4 to $9) or Kroger ($4 to $10)
• Switch to 90-day fills if your pharmacy offers them for under $25
• If you have a Costco membership and fill other medications there, consolidate metformin at Costco for convenience

If already taking metformin IR but experiencing persistent GI side effects:

• Try taking IR with food (if you weren't already)
• If that doesn't help, ask your provider to switch you to ER
• Fill ER at Costco ($9 to $18) if you have membership, otherwise Walmart ($8 to $16)
• If ER costs over $30 at your pharmacy, consider staying on IR and managing side effects with dietary changes (lower fat intake, smaller meals)

If already taking metformin ER:

• Fill at Costco for lowest price ($9 to $18)
• If you don't have Costco membership, check if the annual savings justify the $60 membership fee (break-even is 4 to 5 fills per year)
• If not, use Walmart ($8 to $16) or check local independent pharmacies

If uninsured with very limited budget:

• Immediate-release at Walmart or Kroger: $4 to $10 per month
• If even $4 per month is difficult, contact local FQHCs or free clinics (most provide metformin at no cost for qualifying patients)
• Avoid CVS and Walgreens (2x to 6x more expensive)

If you have insurance but high deductible:

• Don't use your insurance for metformin (cash price is almost always cheaper than your deductible-applied price)
• Pay cash at Walmart or Kroger
• Save your insurance for expensive medications where the deductible spend is worthwhile

If switching from brand-name Glucophage:

• Ask your provider to rewrite the prescription as "metformin" with substitution allowed
• Fill at Walmart or Kroger
• Expect zero difference in effectiveness or side effects
• Save $100+ per month

FAQ

How much is metformin 1000 mg without insurance? Generic metformin 1000 mg costs $4 to $30 for a 30-day supply without insurance at major U.S. pharmacies. Walmart and Kroger offer the lowest prices at $4 to $10, while CVS and Walgreens charge $15 to $30. Extended-release formulations cost $8 to $45.

Is metformin free for uninsured patients? Metformin is not free through manufacturer programs or coupons, but uninsured low-income patients can access it at no cost through Federally Qualified Health Centers, free clinics, or Medicaid if they qualify. For others, the $4 to $30 cash price makes assistance programs unnecessary.

What is the cheapest pharmacy for metformin without insurance? Walmart and Kroger consistently offer the lowest metformin prices at $4 to $10 per month through their generic prescription programs. Costco is competitive at $6 to $11 but requires a $60 annual membership. Publix offers a flat $7.50 price with no membership required.

Does GoodRx make metformin cheaper? Not at Walmart or Kroger, where GoodRx coupons actually cost $3 to $5 more than direct cash prices. GoodRx can save $4 to $10 at CVS and Walgreens. Always check the pharmacy's cash price before using a GoodRx coupon for metformin.

How much does metformin ER cost without insurance? Extended-release metformin 1000 mg costs $8 to $45 without insurance, roughly double the immediate-release price. Costco offers the lowest ER pricing at $9 to $18, while Walgreens charges $28 to $45.

Is brand-name Glucophage better than generic metformin? No. Generic metformin and brand-name Glucophage are bioequivalent and produce identical clinical outcomes. Glucophage costs $120 to $180 per month compared to $4 to $30 for generic, with zero therapeutic advantage. Multiple studies confirm no difference in effectiveness or side effects.

Can I get a 90-day supply of metformin without insurance? Yes. Most pharmacies offer 90-day supplies at 2x to 2.8x the 30-day price. Walmart charges $10 to $20 for 180 tablets, Amazon Pharmacy charges $12 to $18, and Costco mail-order charges $15 to $25. This saves $2 to $20 per quarter compared to three 30-day fills.

Why is metformin so cheap compared to other diabetes medications? Metformin's patent expired in 1994, it's a simple small-molecule drug that costs about $0.07 per tablet to manufacture, and 15+ generic manufacturers compete on price. It's also included in pharmacy loss-leader programs. Newer diabetes drugs like semaglutide are still patent-protected and cost $80+ per dose to produce.

Does insurance make metformin cheaper than cash price? Usually not. Most insurance plans place metformin on low-tier formularies with $5 to $15 copays, but if you haven't met your deductible, you pay the full negotiated price (often $20 to $40). The $4 to $10 cash price at Walmart or Kroger is typically cheaper than using insurance.

What happens to metformin prices during shortages? During the 2024-2025 metformin ER shortage, prices increased 40% to 120% at most pharmacies. Immediate-release metformin saw smaller increases (10% to 25%) in affected regions. Costco and independent pharmacies maintained more stable pricing. Filling 90-day supplies when available helps bridge shortage periods.

Can I use a manufacturer coupon for metformin? No manufacturer coupons exist for generic metformin because it's produced by 15+ companies that compete on price rather than copay assistance. Brand-name Glucophage has a savings program, but it only applies with commercial insurance and reduces copays to $40 to $60, still far more than generic cash price.

Is metformin cheaper at Costco or Walmart? For immediate-release metformin, Walmart is slightly cheaper ($4 to $9 vs $6 to $11), but the difference is minimal. For extended-release metformin, Costco is cheaper ($9 to $18 vs $8 to $16 at Walmart). If you already have a Costco membership, consolidating all prescriptions there is convenient even if not always the absolute cheapest.

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