We are having a very low key wedding and getting married in a registry...

We are having a very low key wedding and getting married in a registry office, followed by a meal with 30 of our family and close friends, just before Christmas this year. We would then like to have a big party with around 120 of our friends in January 2019. My question is, how would you word the invitations to the party? I’d like to avoid the word ‘wedding’ or ‘evening reception’ because we’re not getting married on that day but want to make it clear that it’s to celebrate our marriage and that it’s a proper party with food and a DJ etc. I suppose it would be similar to people having a party after they got married abroad? What wording are you using? Thanks x