A Gold Coast couple has won a landmark court case in a dispute over a prepaid funeral plan, in a decision that could affect up to 19,000 other Queenslanders and their families.

Gavin and Fiona Turner refused to pay the $7,195 bill for his mother Beryl's funeral in 2012, arguing she had already covered the costs through a prepaid agreement she began in 1948.

Beryl Turner had been issued a certificate by Alex Gow Funerals after her final payment in 1980, which stated she was entitled to a funeral service "without further payment".

Alex Gow Funerals sued Mr and Mrs Turner on the grounds the 25 pounds his mother paid the company between 1948 and 1980 was not enough for even the most basic of funeral services today.

The company had offered the family a $390 discount but Beenleigh Magistrate Joan White today found the decades-old agreement should be honoured.

"Nowhere in the agreement does it state that 25 pounds would be deducted from the funeral costs. The deceased was still entitled to funeral services," Magistrate Joan White told the court.

Beryl Turner was presented with a certificate stating she was entitled to a funeral service "without further payment". ( ABC News )

Mr Turner's lawyer, Robert Burns, said more than 19,000 other Queenslanders had signed up to the same agreement, and today's judgment could set a precedent.

"There would have been thousands and thousands of other people who paid for funerals they didn't have to pay for," Mr Burns said.

"It's going to have significant impact on the funeral industry across the board," he said.

"There are thousands of these policies in existence, and it's really going to send a message to funeral homes that they can't promote these types of products without honouring the commitment contained in the document."

Mr and Mrs Turner were overseas for the decision but their children were present and welcomed the verdict.

"It's hard after Grandma's passing to have this hanging over us, and it's just nice to know we can lay her to rest and this is all done," Bradley Turner said.

"She always said 'when I pass, you won't have to worry'," he said.

Gavin Turner had told the ABC's 7.30 program the case made the mourning process much more difficult for his family.

"It's hard, in all honesty, to put mum to rest when you think this court case and all the legal comings and goings are still very much in play," Mr Turner said.

"If I can stop one or two more families in Queensland from having to deal with this, then I feel that us bringing it to light has been a very decent outcome," he said.