I've always simply written it "Happy birthday!" but my wife recently said that "Birthday" should be capitalized as well. What's grammatically correct?


10 Answers 10


... my wife recently said that "Birthday" should be capitalized as well.

In your case, the correct answer is, "Whatever your wife says."

For the rest of us, it seems to be the convention that we capitalize the name of the event in standard phrases of felicitation. E.g.

Happy Birthday

Happy Anniversary

Merry Christmas, and a Happy New Year

This is an exception to the normal rules of capitalization.

  • I mostly agree, except that I have never seen the phrase "Happy Silver Wedding Anniversary", and I don't think I ever will (outside of this context.) "Happy Anniversary!", yes, or "Happy 25th Anniversary!" - accompanied by a gift of silver, of course. But most people won't put the word "wedding" into that phrase (whether capitalized or not), and nobody puts the word "silver" into it either. There are probably a thousand Hallmark cards with this exact phrase as counterexamples, but I submit that ordinary humans (not employed by Hallmark) would not write such a thing.
    – MT_Head
    Oct 19, 2012 at 7:50
  • I do realize that French uses the same word for both "wedding anniversary" and "birthday", and that even in English anniversary can mean any yearly commemoration... but in usual English usage, "Happy Anniversary" only means one thing, and it sounds very unnatural to load it with qualifiers.
    – MT_Head
    Oct 19, 2012 at 7:53
  • Yes, you're quite right. "Happy Anniversary" is much more common. I've amended my answer.
    – Pitarou
    Oct 19, 2012 at 15:21
  • Imagine having texted a wholehearted bIRtHdAy wish and getting redirected to this page. Dec 12, 2021 at 16:50

When you're simply using the two word phrase as in, "Happy Birthday, Nick!" it would be capitalized. However, if you wrote, "He had a very happy birthday, I enjoyed it." It would not be capitalized.

This is one of those odd exception phrases that is capitalized outside of the general rules.

  • Hmm, conflicting advice with @LittleBrother's comment below. Not sure who's right (if there is a "right" answer).
    – Voodoo
    Apr 28, 2011 at 19:04

There's some good advice in the answers here, and there's advice that's absolutely wrong. The answer generally comes down to context, and there are also a lot of situations where you can pretty much do whatever you want. Unless you're writing a birthday card to your English teacher.

In a sentence, "happy" and "birthday" are capitalized according to the normal rules of capitalization: Capitalize the first word of the sentence and any proper nouns.

I hope you have a happy birthday.

Happy birthday to you!

Happy birthday!

When used alone (what this question is asking), you can either treat "happy birthday" as a title, or you can treat it as a fragment. In either case, you have some wiggle room.

Capitalize either all words, or all important words (excluding of, the, and so on). This is sometimes called "title case." When done in the middle of nowhere for no obvious Reason, I think of this as Case of Particular Importance, or Precious Case.

So we'd have:

Happy Birthday

Nick's Birthday Party

Please note that some complete sentences may also be capitalized in this form. Greeting cards are as much about design as they are about grammar.

Cards and advertising headlines frequently throw capitalization rules out the window in favor of what looks cool. (In advertising design courses in school, we were essentially told: It's what people do. Deal with it.) Please don't wince if you see the following:

It's Your Birthday And You're How Old, Exactly?

I Wanted To Buy You A Card To Wish You A Happy Birthday, But I Was Too Cheap

Bottom line:

Capitalizing words in the middle of nowhere is positively weird, but people do it all the time. There are no hard-and-fast rules to cover this, only common usage. Common usage is fairly inconsistent.

So you can either go by regular English capitalization rules or you can do what card designers do and capitalize what looks cool. Pick one and stick with it.

Or you can write your message in ALL CAPS and bypass this problem entirely.


  • I 'm not a member of Linguistics, but I followed a thread and ended up there, at an article where we'd both contributed in its ELU incarnation. . You say 'I've never seen a single style guide advocating mixed practices within the same document' OWTTE, but obviously they are not addressing documents dealing with punctuation styles, where quotes have to be absolutely precise, and contrasts are bound to be needed. Oct 2, 2016 at 15:54

From the context, it is clear that you refer to a greeting. Therefore, the subject of the greeting is, understandably, capitalized. Note that it's usually a phrase, not a sentence by itself.

Happy B irthday!
Happy A nniversary!

Best W ishes!
Finest R egards
Sincerely Y ours,


The salutation is usually rendered 'Happy Birthday' for the same reason that 'Treasure Island' is 'Treasure Island' and not 'Treasure island' or 'treasure island' - usage decrees that not only proper nouns, but also titles, headlines, first lines of poems, and standard phrases of felicitation be given increased emphasis / prominence by capitalisation of lexical words.

Nowadays, we often use quote-like structures for report structures, with the same verbs, so I would argue that the following are all quite acceptable:

She wished him "Happy Birthday!"

She wished him Happy Birthday. [report structure mimicking quote structure]

She wished him a happy birthday.

She wished him "Merry Christmas and a Happy New Year!"

She wished him Merry Christmas and a Happy New Year.

She wished him a merry Christmas and a happy New Year.


If I were sending a friend an email on her birthday, I would write:

Happy birthday, Mary. I hope you have a great day!

  • Hi! Welcome to ELU! Please see How to Answer Questions. Specifically, try to answer the question as asked ("What's grammatically correct?"), preferably with evidence to support your answer. Apr 23, 2013 at 21:27

Birthday can be a common noun or an event. I often capitalize it in a sentence, as if it were an event. I think this is why I am able to get away with it. Either that, or it is because most people do it every which way. I do like the appearance better. Many people don't write a comma before the person's name.......

Happy Birthday, Dale! Happy birthday, Dale! Happy birthday Dale! Happy Birthday Dale!


If used as a two word sentence in the body, then you are correct not capitalizing the "b" in "birthday." However, if it is the title of something, then you would capitalize both letters. So, for example, it is appropriate to capitalize both words in the in the title of the Cracker song "Happy Birthday to Me." It is not appropriate to capitalize it in the sentence: "I want to wish you a happy birthday," or "'Happy birthday!' was the last thing I heard him say."

  • I do think that it should be "I want to wish you a Happy Birthday" since you are using the expression "Happy Birthday".
    – masarah
    Apr 28, 2011 at 5:44
  • @masarah why is the expression "Happy Birthday" and not "Happy birthday" ? Jan 18, 2012 at 17:32
  • For the same reason that 'Treasure Island' is 'Treasure Island' and not 'Treasure island' or 'treasure island' - usage decrees that proper nouns, titles, headlines, first lines of poems, and standard phrases of felicitation be given increased emphasis / prominence by capitalisation of lexical words. Oct 19, 2012 at 9:59

"Happy birthday" because birthday is not a proper noun. Compare it to New Year's Day.

  • 1
    No, you're wrong. Go and have a look at some greetings cards.
    – Pitarou
    Oct 19, 2012 at 6:05
  • 2
    @Pitarou I didn't know that greeting cards are serious sources which confirm our opinions. Do you have any reliable source which states that Happy Birthday is a proper noun or is it just your best guess?
    – Em1
    Oct 19, 2012 at 8:57
  • @Em1 Happy Birthday is not a proper noun. We just capitalize it.
    – Pitarou
    Oct 19, 2012 at 15:28

My fourth grade teacher taught me that it's "Happy Birthday, Mary!" And that's that.

  • 2
    Why should we trust you or your fourth grade teacher? Can you present actual evidence? Jul 27, 2014 at 0:38

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