More than one million people paid more than they needed to for prescriptions in the last year, according to consumer champion Martin Lewis.
The founder of website MoneySavingExpert says hundreds of thousands of patients missed out on average savings of £40 a month because they did not use a prescription 'season ticket'.
The Prescription Prepayment Certificates typically offer savings to those who need to pay for more than one prescription a month.
But according to information from the NHS Business Services Authority - and discolosed to the consumer champion website under a Freedom of Information request - 1,063,648 people paid for at least 12 prescriptions in the last 12 months with 16 being purchased on average.
The current NHS presription charge is £9.35 and was £9.15 for the financial year 2020/21 while patients could then make a single payment of £105.90 - now £108.10 - for unlimited prescriptions.
With more than a million people failing to take out the saving certificates this lead to an average overspend by those patients of at least £40 - or £43 million in total, say those at MoneySavingExpert.com
Founder Martin Lewis said: "England is the only one of the four UK nations that charges for prescriptions, and so it's frustrating to hear that many people are still paying more than they need to – especially at a time when every penny counts towards bills.
"We need to spread the word to anyone who regularly gets prescriptions – including some with chronic illnesses – to check out prepayment certificates."
Buying a pre-paid certificate
Patients who, on average, need to cover the cost of more than one prescription a month are those most likely to save money from purchasing a pre-paid prescription certificate.
Martin Lewis explained: "My simple rule of thumb is if you get more than one prescription a month, on average these 'season tickets' are the cheapest option as they cap what you need to pay. For a one-off payment, you get unlimited prescriptions for either three months or a year.
"So someone getting, say, two prescriptions a month would save over £100 a year. If you think that's you, check it out now in case we see another price hike at the beginning of spring."
The current cost of a Prescription Prepayment Certificate is currently £30.25 for 3 months or £108.10 for 12 months.
According to the NHS Business Services Authority someone using at least two prescriptions each month stands to save more than £115 a year with a certificate valid for 12 months or more than £25 with a three month pass.
While someone who may require four prescription medicines a month can save more than £340 a year with their own prepayment certificate or £75 if they bought one for just three months.
Those wishing to take out a certificate for themselves can buy online - giving them a digital pass to use when purchasing their medicines - or the order can be made over the telephone by calling 0300 330 1341 or by visiting one of the many pharmacies permitted to sell PPCs.
Patients can either pay the amount up front using a bank card, while there are also some direct debit options too to help support those who wish to spread the cost.
Martin Lewis is advising anyone that is considering buying a PPC does so as soon as possible, as season ticket prices and prescription charges tend to rise every April - albeit the costs for the 2022/23 financial year have not yet been confirmed.