The district council gives a twenty five percent council tax discount to more than 22,500 households where there is only one adult resident at the property.
In the last financial year, this totalled more than £6.4million.
The council will shortly be working with a third party to compare its council tax information with other databases.
This will identify those cases where more than one adult is living at an address and a discount is being claimed.
Adrian Sibley, the council’s Section 151 Officer, said: “We know that the majority of our residents will be claiming the discount honestly and legitimately, however, there are times where circumstances change and people forget to tell us their discount should end.
“Also, unfortunately there will be a minority who do attempt to defraud the system.
“We will shortly be sending a letter to residents in receipt of Single Person Discount.
“We will be asking for them to confirm their current circumstances.
“Residents can respond via text, online or by returning the form to the address provided.
“It is a statutory requirement for council tax payers to tell us within twenty one days if they think they should no longer qualify for a discount.
“If you receive a discount you think you are no longer entitled to, this is your chance to tell us before we contact you.
“We are obliged to amend any records we find to be incorrect, back to the date of the change.
“This means that householders do not benefit from withholding information from us and it makes the system fairer for everyone.
“It could mean some households will find they have a considerable amount of council tax arrears to pay.
“Whilst we are cracking down on the incorrect discounts granted, we are still keen to make sure that everyone gets the reductions they are entitled to.
“You should contact us if you think you should qualify for any discounts and exemptions.”
• Residents can contact East Lindsey’s Council Tax team via email at [email protected] or by phone on 01507 601111 and select Option 4.
For more information about the available discounts and exemptions, visit www.e-lindsey.gov.uk/CouncilTaxReductions