# GLP-1 Sellers Billing Every Four Weeks: Thirteen Charges a Year | This GLP How many GLP-1 sellers bill on four-week rather than calendar-month intervals, what the thirteenth charge costs, and why two prices are not comparable without it. Publisher: This GLP Editorial Team Canonical: https://thisglp.com/research/glp1-four-week-billing-cycles Updated: 2026-10-26 Published: 2026-09-15 [← Research](https://thisglp.com/research) Formats # GLP-1 Sellers Billing Every Four Weeks: Thirteen Charges a Year Some GLP-1 sellers bill every four weeks rather than by the calendar month. That is a thirteenth charge a year, roughly an eight percent premium, and it never appears on the price tag. [This GLP Editorial Team](https://thisglp.com/about)September 20264 min readUpdated September 2026 Calendar months billed in a year · Four-week periods billed in the same year · +1 **Research, not medical advice.** This GLP is independent and educational. Nothing here is a substitute for individualized care from a licensed clinician, and reading it creates no doctor–patient relationship. Talk to your own provider before starting, stopping, or changing any medication, peptide, or therapy. See our [methodology](https://thisglp.com/methodology) and [terms](https://thisglp.com/terms). ## Key takeaways - 34 sellers on this roster record a billing interval that is not a calendar month. - 24 of them bill every four weeks, which is thirteen charges a year rather than twelve. - At the median published figure of $190, that thirteenth charge is $190 a year nobody sees on the price tag. - Longer intervals exist too — eight weeks, twelve weeks, and a handful billing weekly. - Counts come from each seller's own recorded note, read most recently October 2026. A price quoted “monthly” is usually a price per calendar month. Sometimes it is not, and the difference is invisible at the point a reader compares two numbers. ## Thirteen is not twelve A seller billing every four weeks charges thirteen times across a year, because fifty-two weeks divides into thirteen four-week periods rather than twelve. That is roughly an eight percent premium over an identical figure billed by the calendar month, and it never appears on the price tag — the same class of gap that [the disclosure scorecard](https://thisglp.com/tools/what-sellers-publish) marks sellers on. At this corpus’s median published figure of $190 a month, the thirteenth charge is $190 a year. 24 sellers here record a four-week interval in their own pricing notes. 34 record some non-monthly interval in total, including 3 every week, 1 every eight weeks, 6 every twelve weeks. These counts are a floor There is no billing-interval field on this roster. A seller appears in these counts only when its own recorded note names the interval, so a seller absent from them has not been shown to bill by the calendar month — it has simply not written the interval down anywhere this desk has read. Inventing a value from that silence is the error this site refuses to make. ## The longer intervals cut the other way Twelve-week billing is the mirror image: fewer, larger charges rather than more, smaller ones. It is not a premium, but it is a commitment, and a reader who stops treatment partway through a quarter has usually already paid for it. Neither interval is dishonest. Both make two published figures non-comparable until the interval is read alongside them, which is why [the questions worth asking](https://thisglp.com/tools/questions-they-leave-open) start with the terms rather than the number. ## Reading the interval first [The billing cadence check](https://thisglp.com/tools/billing-cadence-check) lists every seller whose own note names an interval, with the charges a year each implies. It is the first thing worth reading on any seller whose figure looks competitive, because a number that turns out to be per four weeks is not the number it appeared to be. For the sellers that publish every rung of a ladder instead, see [published dose ladders](https://thisglp.com/tools/published-dose-ladders). Counts are computed from this site’s own records at build time, most recently read October 2026. Not every nonmonthly supply is a recurring four-week charge. [Henry Meds’ review](https://thisglp.com/reviews/henry-meds) distinguishes monthly billing from shipment allowances: its [program terms](https://henrymeds.com/legal/programs) describe semaglutide quantities over 70- or 90-day windows. Read the payment frequency and shipment window separately rather than deriving one from the other. ## Frequently asked How much does four-week billing actually add? About eight percent over a year, because thirteen four-week periods fit into fifty-two weeks rather than twelve. At this corpus's median figure that is roughly one extra monthly charge annually. Is a seller missing from the list billing monthly? Not established. There is no billing-interval field; a seller appears only when its own note names the interval. Absence means nothing was written down, not that the interval is a calendar month. Is twelve-week billing better? It is fewer, larger charges rather than more, smaller ones — not a premium, but a commitment. A reader stopping partway through a quarter has usually already paid for it. ## Sources ## Where to get it ### Best GLP-1 injections Every injectable seller we can verify, with the price each one publishes and an honest read of what the trials measured. [Compare providers →](https://thisglp.com/best/compounded-semaglutide) ## More in Formats - [ Label-approved sites and semaglutide exposure · Abdomen · 2 in. from navel · similar · Thigh · under the skin · similar · Upper arm · under the skin · similar · Blood levels, not weight loss. No trial randomized people to a site. ### Where Should You Inject Ozempic? Abdomen, Thigh or Arm Gave the Same Exposure ](https://thisglp.com/research/where-should-you-inject-ozempic) - [ The labeled ladder — four weeks on every rung · 0.25 · wk 1–4 · 0.5 · wk 5–8 · 1 · wk 9–12 · 1.7 · wk 13–16 · 2.4 · wk 17+ · Milligrams weekly. No compounded product carries this label. ### Semaglutide Starting Dose: 0.25 mg, and What Compounding Changes ](https://thisglp.com/research/semaglutide-starting-dose) - [ Approved: weight management, US, April 2026 · Phase 3 in progress, not approved: · sleep apnea · hypertension · urinary incontinence · osteoarthritis pain · artery disease · A daily tablet, not a peptide, not an injection. ### Is There a GLP-1 Pill That Works? Two Tablets, Two Different Answers ](https://thisglp.com/research/does-the-glp1-pill-work-as-well-as-the-injection)