Two P.E.I. marriage commissioners are offering free marriage vow renewals for couples who have been married for 50 years or more this year.

Diana Lariviere and William Caw, owners of Weddings PEI, are making the offer as a way to celebrate Canada's 150th birthday.

"Fifty years of marriage seems to be one of the primary landmarks for couples," said Lariviere.

"We figured that 50 years would be a nice cut-off point, and it's also one of the figures that is in 150."

Normally the ceremony would cost a minimum of $175. The only qualification is that the couple is celebrating 50 years of marriage or more in 2017.

Lariviere said people might have to cover the cost of gas, depending where they want the ceremony to take place.

They have had one inquiry so far, but expect interest to pick up in the summer.