GoodRx, Amazon Pharmacy & Cost Plus Drugs — Paying Less for Prescriptions

Why prescription prices finally became shoppable

For decades, nobody could see the menu. Every pharmacy set its own cash price, every insurance plan cut its own deals, and the person at the counter just paid whatever the register said. That's changed. Free tools like GoodRx and SingleCare now show the discounted cash price at every pharmacy near you. Mark Cuban's Cost Plus Drugs publishes its actual cost plus a flat 15% markup, a $5 fee, and shipping. Amazon's RxPass covers a whole list of common generics for $5 a month if you're a Prime member.

None of this is a trick, but there is fine print — and it matters most for folks on Medicare. Paying cash with a coupon means the purchase is invisible to your drug plan: it doesn't count toward your deductible, and it doesn't count toward Medicare Part D's yearly out-of-pocket cap ($2,100 in 2026). Saving $8 on a cheap generic is usually fine. Taking an expensive drug outside your plan can cost you real money by December. This guide covers both halves: how to save, and when not to.

The three big tools, in one paragraph each

• GoodRx (free). A price-comparison site with coupons attached. Look up your drug at goodrx.com, print or show the coupon at your regular pharmacy, and pay a discounted cash price instead of your copay — whichever is lower. Best on generics. Paid tiers exist (GoodRx Gold at roughly $10/month, and the newer $14.99/month GoodRx Companion), but most retirees do fine with free.
• Cost Plus Drugs. Mark Cuban's online pharmacy shows the math on every price: the drug's actual cost + 15% + a $5 pharmacy fee + shipping (from about $5.25). Mostly generics, mostly mail order — ideal for the boring monthly forever-pills. A free Team Cuban Card brings similar pricing to Kroger, Meijer, Albertsons and many independent pharmacy counters.
• Amazon Pharmacy + RxPass. A real licensed mail-order pharmacy inside Amazon. RxPass adds a flat $5/month (on top of Prime) for as many medications from its generics list as you're prescribed, delivered free. Check the fine print: not offered in every state, and folks on Medicaid currently can't subscribe — Medicare beneficiaries can.

The one rule that governs all of it

On any single fill, you use either your insurance or a discount coupon — never both together. You're free to choose per drug and per refill: insurance for the expensive brand, a coupon for the cheap generic, mail order for the maintenance pill. But because a coupon fill is a cash sale, your insurer never sees it — no deductible credit, no progress toward any out-of-pocket cap. That's the entire catch, and once you know it, the decision gets simple.

On Medicare? Here's the part to slow down for

Since 2025, Medicare Part D caps your yearly out-of-pocket drug spending — the 2026 cap is $2,100. Only spending that runs through your plan counts toward that cap (Medicare calls the running total TrOOP). Cash coupon fills never count. So the rule of thumb: cheap generics by coupon are usually harmless, but keep expensive drugs on the plan so you march toward the cap. If your medication list is mixed, twenty minutes with your pharmacist or a free OSHIIP counselor in January is worth more than any app.

The ask-the-pharmacist script

You don't need an app to start saving. Before they ring you up, ask: "Is there a cheaper way to buy this — would the cash price or a discount card beat my copay?" Pharmacists field this question all day and many will run a discount card for you on the spot. Etiquette that keeps it friendly: ask before the sale, pick a quiet mid-morning moment, limit it to a drug or two per visit, and take the answer graciously — sometimes insurance wins, and that's a good visit too.

The kitchen-table worksheet

The heart of the printable guide is a one-page worksheet: one row per medication, with columns for your current copay, the GoodRx price, the Cost Plus price, and your decision. Fill it in once with your pill bottles in front of you, show it to your pharmacist before switching anything, and redo it every January when plan copays reset. It doubles as the complete medication list every doctor and pharmacist should see.

Watch out for the fakes

• Any "pharmacy" that sells prescription drugs without a prescription is not a pharmacy. Walk away.
• Prices dramatically below even Cost Plus — especially on brand names — are bait.
• No U.S. address, no phone number, no pharmacist to talk to: bait.
• Payment by gift card, wire, or crypto: always a scam, in every industry.
• Type addresses yourself (goodrx.com, costplusdrugs.com, pharmacy.amazon.com). Never reach a pharmacy through a link in an email or text.

What's in the printable PDF

• Why the same pill has five prices — and a side-by-side table of all the savings tools.
• The one rule: coupon OR insurance, never both on the same fill.
• GoodRx step by step, from lookup to counter — including the paper-coupon route if you don't use a smartphone.
• GoodRx Gold and the new Companion subscription — when paying monthly makes sense and when it doesn't.
• Cost Plus Drugs: the cost+15% model, ordering step by step, and the free Team Cuban Card for in-person pickup.
• Amazon Pharmacy and RxPass — the $5/month math, the generics list, and the state and Medicaid fine print.
• On Medicare? The page to read first: the 2026 $2,100 cap, TrOOP, and why cash fills don't count.
• When a cash coupon beats your copay — four common situations, one table.
• The word-for-word ask-the-pharmacist script, plus the etiquette.
• SingleCare, WellRx, and where to turn if money is genuinely tight (Extra Help, assistance programs).
• The fill-in price-comparison worksheet — one row per medication.
• Spotting fake online pharmacies, mail-order habits that work, a plain-English glossary, and a cut-out fridge card.

Why I wrote this

I'm not a pharmacist and I don't sell insurance — I'm the tech guy, and I get nothing whichever tool you pick. But a lot of my visits end with someone asking about "that GoodRx thing" or whether the Mark Cuban pharmacy is real, and the honest answers take more than a minute — especially the Medicare part, which most articles skip entirely. So I wrote it all down the way I'd explain it at a kitchen table, with a worksheet you can actually fill in. The medical and money decisions stay with you, your pharmacist, and your doctor. — Bill