Are there general guidelines for using "anniversary" vs. "birthday"?

E.g., birthdays are generally for... well, birthdays. It's also used for some notable historical dates regarding countries ("Our nation's birthday") and cities.

Is there a meaningful, generally-accepted differentiation?

  • The same as with car vs. vehicle. It's a hyponym, not a synonym. The former is one type of the latter.
    – RegDwigнt
    Commented Aug 25, 2014 at 19:01
  • Note that very confusingly in 1/2 ?? of other european languages there's no specific word for "birthday", there's only an "anniversary" analogue. Confusing.
    – Fattie
    Commented Aug 25, 2014 at 19:03

5 Answers 5



  • using the stricter definition, a birthday is the anniversary of one's birth.


  • is a word used to commemorate special occasions, like weddings, or first dates ( important job promotions for instance) or important purchases ( a house) and things like that. Interestingly enough, even though we don't usually refer to birth dates as "anniversaries" ( unless we are referring to famous people) we do use the word when referring to death dates.

    • The 100th anniversary of the birth of composer Benjamin Britten.

    • Taoiseach commemorates 90th anniversary of Michael Collins’ death

  • RHK Webster's adds the broader definition for 'birthday': 3. a day commemorating the founding or beginning of something. (Collins adds the even broader 'any anniversary', but I think this is a very rare usage.) Commented Aug 25, 2014 at 19:09

Anniversary is for things that are celebrated annually. And this includes birthdays, of course, but a birthday is a special case of anniversary, and you would almost never say birth anniversary, but almost always birthday.

However, unless you qualify the anniversary, it is generally taken to mean a "wedding anniversary". If I say, "Today is my anniversary," unless the context clearly indicates otherwise, I would be speaking of my wedding anniversary.

So, for other anniversaries, use a qualifier. For my employment I would possibly say "work anniversary" or something similar.

For notorious anniversaries, such as a nation's birthday, we seem to usually use a recognized proper name. For the United States, July 4 is referred to as "Independence Day." In France an important anniversary is "Bastille Day". In New Zealand, "Dominion Day."

  • Countries aren't all bad. Commented Aug 25, 2014 at 19:02
  • Of course the Queen has various birthdays. The 21st April, when she was 88 this year, is the anniversary of her birth in 1926. However her 'official birthday' is always on a Saturday in June, when the Trooping of the Colour is performed. Neither of these are a public holiday in Britain. However the Queen's birthday IS a public holiday in Australia. All states other than Western Australia commemorate this on a date in June, but in WA it is always on a date in September, this year the 29th. Don't ask me why WA is different.
    – WS2
    Commented Aug 25, 2014 at 19:08
  • It's those Perthites, @WS2. Odd bunch. You got to wonder about folks who turn all their lights on just so US Astronaut John Glenn will see their city as he goes by overhead. Both times. 35 years apart. Commented Aug 25, 2014 at 21:34
  • @EdwinAshworth - On 14 October 2066, the English will be able to celebrate a full 1000 years of independence from the Anglo-Saxon yoke.
    – Erik Kowal
    Commented Dec 13, 2014 at 7:13
  • 1
    @ErikKowal, are you sure the English would want to celebrate the brutal conquest of William I, who dispossessed the native Anglo-Saxon nobility cum royalty with a Norman one, and forever changed the common language? :-) Commented Oct 1, 2015 at 17:07

Birthday is generally used for people's birth dates and sometimes for a country's, as you've said. Anniversary, on the other hand, is generally used for a marriage or relationship between two people, for example the day of the year two people got married. It is also used to signify the day an important event happened. For example, November 9th of this year will be the 25th anniversary of the Berlin Wall coming down.


In some instances (e.g., news) birth anniversary is also used to refer to someone's birthday after their passing (death).

E.g., James shared a prayer in honour of his late friend Brock on his birth anniversary. Brock passed away due to COVID-19 in 2020.


My idea ...anniversary is when you take the total age - years, say 50th anniversary. you can also say 50th birthday, but in general it's awkward ...you say birthday when your focus of significance is the DATE not the AGE ...this goes well with institutions since the age is associated with longevity.

  • Welcome to English Language & Usage @stdennismatthew. Your post would be improved if it was supported by references and an explanation of why it answers the question.
    – user63230
    Commented Dec 13, 2014 at 8:16

Not the answer you're looking for? Browse other questions tagged or ask your own question.