The study carried out among 2,000 married people found that a whirlwind first year of being swept along in a tide of post-wedding happiness is followed by a year of getting to know each other.
But the third year marks the point in the partnership when, having overcome the occasional doubt and learned to deal with each other's imperfections, couples begin to settle into a comfortable co-existence, researchers said.
It's also around this time that plans to add to the family are likely to be discussed, further cementing the relationship.
Enjoying the luxury of two salaries also makes this an enjoyable time along with the fact that renovations or improvements to the marital home are likely to be close to completion.
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In contrast, the study found the fifth year to be the hardest to overcome due to factors such as tiredness or even exhaustion amid increasing workloads.
"It's not very often that we see clients in those first few years of marriage but by the five year mark or a couple of years after they have children we often have married couples asking us for advice," Amanda McAlister Family Law Solicitor at Slater & Gordon said.
Familiarity with each other, regular bickers over the sharing of chores and the stress caused by financial worries surrounding caring for a young child all begin to take their toll around the five year point.
But respondents voted seven years to be 'the wall' which if scaled successfully paves the way for a long, happy and lasting liaison for matrimony.
Indeed a third of people feel there isn't enough affection in their marriage and one in five say there are days when they regret the decision to get hitched completely.
Unbalanced sex drives, different hobbies or social preferences were found to provide stumbling blocks after the first few years, researchers said.
The study found half the 2,000 studied said their wedding day as the happiest of their life and the first year was ranked just behind the third for general happiness.