The Money Saving Expert founder says people who have be paying incorrect rates for a significant period of time could claim the money back.
Speaking on the Martin Lewis Money Show he set out seven steps to work out if you are paying too much, and reclaim what you are owed.
Check your council tax band – here’s how
Up to 400,000 households are overpaying in the wrong council tax band and may be owed repayments going as far back as 27 years.
Martin outlined two steps to reveal whether you are affected.
First of all, check what your neighbours are paying by visiting the Valuation Office Agency (VOA) in England or the Scottish Assessors Association (SAA) in Scotland.
If you are paying more than your neighbours, work out what your house was worth in 1991 with the help of online tools, such as this one from Nationwide.
Once you know the house’s previous value, you can see what council tax band you should have been placed in.
You should only apply for a refund if both checks indicate you are in the wrong band.
On a street in Hull, one unidentified resident appealed as she was in band B and all her neighbours in similar properties were in band A.
But instead of her getting a council tax cut, all her neighbours are now facing larger bills as they were all put into a higher band.
This is why it is vital to also do the valuation check.
Lower occupancy discounts
If you are a single adult living alone, you should get a 25% discount on your council tax.
The full bill usually assumes at least two adults live in a property.
Discounts also apply to students, carers, people with health conditions and children.
Tell the council as soon as possible if your circumstances change through a housemate/lodger leaving, becoming a student, separation, divorce, or the death of a partner/spouse.
You can backdate lower occupancy claims too.
Benefit claimant discounts
People on certain benefits or a low income can receive discounts of up to 100%.
It does not matter if you own your own home or rent, or whether you are employed or not.
All can apply, but the sooner you apply the better as council tax reductions are not typically backdated.
The reduction comes on top of any benefits or universal credit you receive.
Your reduction depends on factors such as where you live, your income, the number of children you have and your residency status.
Some councils may let you backdate the reduction, but by how many months varies by council so you will need to check.
Severe mental impairment discounts
If you or someone you live with is medically certified as being ‘severely mentally impaired’ you could be eligible for a discount.
This is a medical diagnosis in itself, but the underlying cause could be a condition such as dementia (including Alzheimer’s) or severe learning difficulties.
There is a 25% discount if you live with someone with a severe mental impairment and no other adults, or only adults who are also disregarded for council tax purposes.
If you have a severe mental impairment and live alone you receive a 100% discount.
The claims are also backdated, meaning you could receive thousands.
Many councils are offering extra support such as payment holidays for residents who have lost out on income due to the pandemic.
Support is offered on a case-by-case basis, but most would offer payment holidays for those struggling with their 2020/21 council tax bill or give council tax reductions of up to 100% on bills for many people on benefits.
In England, you may also get £150 off your bill backed by a £500 million Covid-19 hardship fund.
Have you adapted your home?
If you have made changes to your home for a disabled resident, you could be eligible for a refund.
Instead of a discount, you may be able to get your council tax band lowered.
Are the council sitting on your cash?
Many people pay council tax a month or a year ahead, meaning if you move house, they keep it until you ask for it back.
If you have moved in the past few years, search for council tax refunds on your old council’s site.