How to Calculate Your Wedding Anniversary: Which Anniversary Is It, the Counting Rule, a Formula and Leap-Day Weddings

Every February a small argument breaks out in the Sharma household. They were married on 14 February 2020. On 14 February 2026, Nisha says it is their sixth anniversary. Her husband says they are in their seventh year of marriage, so surely it is the seventh. Her mother says the first year does not count. Only one of them is correct, and the cake has to say a number on it.

This post is the arithmetic: what a wedding anniversary is, the counting rule, a formula you can do in your head, the anniversary-year names, leap-day weddings, what to do when an Indian wedding has two dates, and the exact days-married figure for captions.

A wedding anniversary is the yearly return of the date you were married. The word comes from the Latin for returning yearly, so it contains the rule: once a year, on the same calendar date, each return marking one more completed year. A marriage anniversary is the same thing; our post on whether marriage anniversary or wedding anniversary is correct explains that both are fine.

One aside, because people mix the two up: a wedding anniversary is the yearly return of a wedding date, a birthday is the yearly return of a birth date. Some people write anniversary when they mean birthday; an anniversary is for an event and a birthday is for a person.

The wedding day is day zero. One year later is the first anniversary, because one full year has been completed. On the Nth anniversary you have been married exactly N years and are starting year N plus one.

That last part is where the off-by-one confusion comes from. On the sixth anniversary you have completed six years and are beginning your seventh year of marriage. Both are true at once: the anniversary number counts completed years, the ordinal year counts the year you are in. So the Sharmas celebrate their sixth anniversary on 14 February 2026 and enter their seventh year. Nisha is right about the cake, her husband about the year, and her mother is confusing the wedding day with a first anniversary, which it is not.

Quick check: the anniversary number is the difference between the two years once the date has arrived. 2026 minus 2020 is 6. If the cake says one more than that, it is wrong.

Current year minus wedding year; if the anniversary date has not yet arrived this year, subtract one more. The result is your most recent anniversary, or, on the day itself, the one you are celebrating.

Worked examples. Married 14 February 2020, checked on 14 February 2026: 6, date arrived, sixth anniversary. Checked on 10 January 2026: 6, but 14 February has not come, so subtract one; the fifth was the most recent and the sixth is coming. Married 25 November 2018, checked on 5 November 2026: 8, date not yet arrived, so the seventh was the most recent and the eighth falls on 25 November 2026.

For the next anniversary instead of the last, add one whenever the date has not yet arrived. A days-together counter does both steps for you.

Once you know which anniversary it is, the traditional names attach to it. The commonly used Anglo-American list runs paper for the first, cotton for the second, leather for the third, wood for the fifth, tin for the tenth, crystal for the fifteenth, china for the twentieth, silver for the twenty-fifth, pearl for the thirtieth, ruby for the fortieth, gold for the fiftieth and diamond for the sixtieth. Our anniversary gifts by year post has the full list with modern alternatives. The one thing to carry over: the name follows the completed-years number, so six completed years means you look up the sixth, not the seventh.

If you married on 29 February, your exact date exists once every four years, so in three years out of four you have to choose between 28 February, the last day of the month you married in, and 1 March, the day after your date would have fallen. For a celebration there is no wrong answer; pick one, keep to it, and make more of the real 29 February when it comes round.

For anything official, the usual convention in most places is to treat the anniversary as 1 March in a non-leap year, on the reasoning that the year is not complete until all of February has passed. Rules differ by country and document, so check the one that applies to you. The counting rule itself does not change.

Many Indian couples have more than one date that could count: the registered marriage may be weeks before or after the ceremony, and a roka or engagement months earlier may be what the families treat as the beginning. Couples who dated first have a dating anniversary too; our post on dating anniversary versus wedding anniversary covers which to keep.

For the count, pick one date and commit to it, because the number only works from a single starting point. Most couples choose the ceremony, the day the families, photographs and memories attach to; some choose the registration, the date on the certificate and every official form. Keep the other as a second celebration with its own name, the court anniversary or the roka anniversary, rather than averaging or alternating. Two small celebrations and one clear count beats one celebration and a yearly argument.

Years are what anniversaries count, but days are what people post. The six-month mark is the half anniversary and the monthly milestones are the monthsary, both covered elsewhere on this site; beyond that, captions use the total number of days, as in 2,190 days married.

Days are awkward to count by hand because of month lengths and leap years. Six years from 14 February 2020 to 14 February 2026 is 2,192 days, not 2,190, because the span contains two leap days, 29 February 2020 and 29 February 2024. A round figure like 2,190 is usually an approximation of six years rather than a count. A days-together counter gives the exact number from your wedding date to today and keeps running, so the tenth-anniversary caption can say 3,653 days and be right, and it will tell you when your 2,000th or 5,000th day falls, which is a better excuse for a dinner than most.

Briefly, the questions we see most often.

Current year minus wedding year; subtract one if your date has not come round yet this year. That is your anniversary, it equals the years you have completed, and it is the number for the gifts list and the cake. Everything else is a matter of picking a rule and keeping it. The Sharmas settled on sixth anniversary, seventh year, and a counter on the fridge that says 2,192 days, so nobody has to do the sum at the table next time.