# Four-week vs monthly medicine prices: a budgeting guide https://www.med-easy.co.uk/guides/four-week-vs-monthly-medicine-costs/ Publisher: Med Easy Source material checked: 2026-10-20 Editorial information; no registered-clinician review is claimed. General UK healthcare information. Country-specific rules and provider examples retain the limits stated in the text. Fees are dated examples, not live quotes. ## Short answer Confirm the quantity and intended supply period before converting a quote into a monthly or annual budget. Four weeks is 28 days, and thirteen such periods cover 364 days. A calendar-month payment may follow a different schedule, so compare actual supply and payment dates rather than treating the labels as interchangeable. “Per month” can describe a billing period, a pack or simply a headline. Establish what the quote actually covers before comparing the number. ## Key points - Twelve four-week periods cover 336 days rather than a calendar year. - Pack quantity and billing period are different inputs. - Budget calculations must not change the prescribed way a medicine is used. ## Use the supplied period, not the marketing label Begin with three facts from the provider: the prescribed product, the quantity supplied and the period that quantity is intended to cover. A daily tablet pack and an injection presentation may be described differently. Do not infer either supply period from the medicine’s name or from the presence of a monthly payment option. The public source summaries used by Med Easy do not always specify pack quantity or supply duration. The AI-readable data therefore leaves the supply period unknown rather than filling in a convenient assumption. Open the original offer and ask the provider to confirm those details before using a budget calculation. Section link: https://www.med-easy.co.uk/guides/four-week-vs-monthly-medicine-costs/#use-the-supplied-period-not-the-marketing-label ## Four weeks and a calendar month are different units Four weeks is 28 days. Thirteen 28-day periods cover 364 days, whereas twelve calendar months cover a calendar year. That arithmetic explains why multiplying a four-week quote by twelve does not describe a full year of continuous four-week supply. As an illustration, £100 for each 28-day period would be £1,300 across thirteen periods. A plan charging £100 per calendar month would collect £1,200 across twelve payments. Neither total says whether the quantity or care is equivalent. These are example figures, not current treatment prices or a prediction of how long you will use a medicine. Section link: https://www.med-easy.co.uk/guides/four-week-vs-monthly-medicine-costs/#four-weeks-and-a-calendar-month-are-different-units ## Compare price per supplied day only when the inputs are confirmed If the provider confirms that a £140 pack covers 28 days under your prescription, its simple quoted cost is £5 per supplied day. A £150 pack confirmed to cover 30 days has the same arithmetic daily cost. Additional required charges and different clinical services still need separate consideration. Do not use this calculation to alter how a medicine is taken, extend a pack or extract extra doses. It is a way to compare quoted quantities. The prescriber and product instructions determine use. If the intended supply period is unclear, the correct next step is a question to the dispensing service. Section link: https://www.med-easy.co.uk/guides/four-week-vs-monthly-medicine-costs/#compare-price-per-supplied-day-only-when-the-inputs-are-confirmed ## Build a calendar of actual expected charges Write down the expected order dates and the amount payable on each date. Add assessment, delivery and review charges on the dates they fall due. A simple calendar can expose a month with two four-week payment dates even when the average cost initially seemed affordable. Keep an introductory discount separate from repeat charges. If a future dose has not been prescribed, use labelled scenarios rather than presenting a dose increase as inevitable. For example, record “current prescribed dose continues” and “clinician changes the plan; quote needed” instead of inventing a medical schedule. Section link: https://www.med-easy.co.uk/guides/four-week-vs-monthly-medicine-costs/#build-a-calendar-of-actual-expected-charges ## A compact worksheet for a useful comparison Use one row per provider and one column for each input: product, dose, quantity, confirmed supply days, order price, additional mandatory costs, renewal timing and quote date. Leave unknowns blank and ask for clarification. A comparison with visible gaps is more useful than a precise total based on guessed quantities. Read the complete treatment-cost guide for a two-quote calculator and subscription guide for payment commitments. The dose tables link to Monj, iGovy, Ogovy and Dayo offer pages, where you can begin checking the product details. Budgeting does not establish treatment suitability or duration. Keep financial planning alongside the clinical plan, and ask the provider what happens to charges when that plan changes. Section link: https://www.med-easy.co.uk/guides/four-week-vs-monthly-medicine-costs/#a-compact-worksheet-for-a-useful-comparison - [complete treatment-cost guide](https://www.med-easy.co.uk/guides/compare-weight-loss-treatment-costs/) - [subscription guide](https://www.med-easy.co.uk/guides/subscription-vs-one-off-weight-loss-costs/) - [dose tables](https://www.med-easy.co.uk/all-dose-prices/) ## Questions to ask - Has the provider confirmed the quantity and intended supply days? - Does “monthly” describe the payment schedule or the medicine supply? - Have I mapped every payment date in the period I am budgeting? - Are one-off assessments and review charges added on their actual dates? - Have I kept uncertain treatment changes as labelled scenarios? ## Frequently asked questions ### Why can four-week payments create two charges in one calendar month? A four-week cycle repeats after 28 days, while most calendar months are longer. Payment dates therefore move through the calendar and can fall twice within one month. Map the actual dates when planning cash flow rather than relying only on an average monthly figure. https://www.med-easy.co.uk/guides/four-week-vs-monthly-medicine-costs/#faq-1 ### Can I calculate a daily medicine cost from the pack price? Only when the supplied quantity and its intended period under your prescription have been confirmed. Divide the quote by those supply days for a budgeting comparison, then account for required extra fees. Do not use the result to stretch supply or alter dosing. https://www.med-easy.co.uk/guides/four-week-vs-monthly-medicine-costs/#faq-2 ### What should I do if the source feed does not state pack duration? Leave the supply period unknown and open the source offer or ask the pharmacy. A dose label does not establish pack quantity or duration. Med Easy keeps missing period information visible so an apparently precise annual total is not built on an invented input. https://www.med-easy.co.uk/guides/four-week-vs-monthly-medicine-costs/#faq-3 ## Sources - [Monj: Mounjaro price comparison](https://monj.co.uk/) — Comparison source - [iGovy: Wegovy injection price comparison](https://igovy.co.uk/wegovy-price-comparison-uk/) — Comparison source - [Ogovy: Wegovy pill price comparison](https://ogovy.co.uk/wegovy-pill-discount-price-list/) — Comparison source - [Dayo: Foundayo price comparison](https://dayo.co.uk/foundayo-discount-prices/) — Comparison source ## Related guides - https://www.med-easy.co.uk/guides/compare-weight-loss-treatment-costs/ - https://www.med-easy.co.uk/guides/subscription-vs-one-off-weight-loss-costs/ - https://www.med-easy.co.uk/guides/reading-live-medicine-price-data/