Honestly, I m thinking no less than 3 years, longer if the couple is in their early 20 s. You want to experience all the sides of that person before committing to them for life. We continue to change throughout our life, though the biggest changes seem to occur in our 20 s and early 30 s. How a person deals with life is very important, how they handle conflict, how they handle finances, how they view life, how well they adjust to changes in life and their views on being a parent. Marriage is so much more than a piece of paper and a name change. It is really easy to get a marriage license, plan a wedding and say I do. Though, when it turns bad it s really hard and expensive to end. No one goes into a marriage expecting it to end and if they do that should be their first sign. There is no need to rush, if a couple is meant to be together a lifetime, they will be together a lifetime with or without a piece of paper bonding them together.