As many as 850,000 families could be missing out on pension credit worth an average of £1,900 per year.
A new report by the Department for Work and Pensions (DWP) revealed that a total of £1.7 billion of pension credit went unclaimed in the 2019/20 financial year.
Here, Which? explains how pension credit works and offers advice on how to claim if you're eligible.
is a weekly benefit that gives you extra money to help with your living costs if you're over state pension age (SPA) and on a low income. It's also a gateway into other benefits such as council tax support and cold weather payments.
There are two parts to pension credit: guarantee credit and savings credit. You may be eligible for one or both.
Only people who reached SPA before 6 April 2016 qualify to claim savings credit. If you reached SPA on or after 6 April 2016, you can still get guarantee credit.
Even if you're only entitled to a few pounds, it's still worth claiming as it may help you quality for other benefits.
Guarantee credit tops up your weekly income to a guaranteed level of £177.10 for single people and £270.30 for couples in the 21/22 financial year.
You must have reached SPA for this benefit - which is currently 66 for both men and women.
To qualify you must live in the UK and have reached pension credit qualifying age (same as SPA). The amount you'll get depends on your income.
Couples are only eligible for guarantee credit once they both reach SPA. If you're in a couple and are not eligible for guarantee credit, you can both apply for universal credit instead.
If you were already receiving pension credit before 15 May 2019 and you're in a couple, you can continue to claim the benefit regardless of your partner's age.
If you're a carer, have severe disabilities or certain housing costs, you might qualify for a higher level of guarantee credit.
Savings credit provides extra money if you've made some provision towards your retirement by saving, or contributing to a pension other than the basic state pension.
The extra income is up to £14.04 a week for a single person or £15.71 for married couples and civil partners. The rates will rise to £14.48 and £16.20 respectively from April.
To qualify you must have a minimum income of £153.70 a week if you're single, or £244.12 a week for a couple.
The DWP says just two thirds (66%) of people entitled to claim in the 2019/20 financial year did so.
The take-up for guarantee credit was 73% - a figure significantly higher than the 43% recorded for savings credit.
The DWP said this disparity could be influenced by the difference in the average weekly amounts people were entitled to.
The estimated average weekly amount unclaimed for guarantee credit was £57, but for savings credit it was just £6.
Those aged under 75 were more likely to claim pension credit (68%) than those over 75 (65%).
It will give you an estimate of any pension credit payment you're due based on your earnings, benefits, pensions, savings and investments.
You can start an application up to four months before you become eligible for pension credit.
If you apply after you reach state pension age, your application can only be backdated by three months.
If you have been previously been turned down because of your savings it's worth having another look, as your circumstances may have changed.
There are three ways to apply, online, by post or phone.
You'll need the following information:
If you already get pension credit and need to inform the DWP about a change in circumstances, you should do this by telephone.
You can contact the pension credit claim line by calling 0800 99 1234.
You can call Monday to Friday between 8am and 6pm. If you cannot hear or speak on the phone call Relay UK on 18001 then 0800 99 1234.
The Pension Service 8
Post Handling Site B
If you apply for pension credit and don't agree with the decision you receive, you may be entitled to appeal against it - this is also known as 'mandatory reconsideration'.