The EL&U’s archives told me ‘thanks’ is slightly more informal than ‘thank you’. I’d like to get a little more specific info.

I’m now reading Harry Potter series and came across the following scene.

“Well, I just thought I’d congratulate you again on your splendid performance against that Horntail, Harry,” said Bagman. “Really superb.”

Thanks,” said Harry, but he knew this couldn’t be all that Bagman wanted to say, because he could have congratulated Harry in front of Ron and Hermione. (Harry Potter 4 [US Version]: p.445)[Bold font is mine]

N.B.: Bagman is the head of a department of Magical Ministry and he is much older than Harry. They are acquainted with each other.

It seems to me that ‘thanks’ can be used in any occasion, even if the speakers are distant in their ages and social positions, but is there any occasion where the word isn’t appropriate? What makes you choose ‘thanks’ over ‘thank you’?

Also, can I use it for answerers and commentators in this site?

I often see ‘thanks’ this site, but I think they might be acquainted with each other in a chat or something. I tried writing ‘Hi, thanks’ a couple of times, but I can’t wipe off a feeling that I might be far too familiar and make people unpleasant.

  • 1
    Although EL&U is a 'community', that doesn't mean we all think the same re appropriate levels of politeness/formality. Do like most people - follow your natural inclinations, paying some attention to the things you see others write. No-one's likely to feel particularly offended even if they do think you're being a bit too informal - and saying "Thanks" in an online forum is hardly likely to be thought excessively informal by anyone. I just write "ty" sometimes. Commented Jul 26, 2011 at 3:28
  • 2
    FWIW, I seem to remember Harry was probably suspicious of Bagman, or at least didn't like him much, and I think he was inclined to be sullen often, especially when talking to someone in a position of authority he didn't like much. That is, I think Harry was being mildly rude by saying "Thanks" rather than something longer, because he (correctly) suspects Bagman's motives. I think to someone he liked he would say "Thanks" enthusiastically, and to someone he respected would probably say "Thank you".
    – Jack V.
    Commented Jul 26, 2011 at 9:12
  • @Jack V. You made my reading a more enjoyable one. Thanks!
    – user7493
    Commented Jul 27, 2011 at 4:19

2 Answers 2


I agree that "thank you" is slightly more formal than "thanks". I suspect if I was addressing the Queen I'd say "Thank you, ma'am". I tend to use "thank you" for emphasis, to show that I am really grateful, and it's not just a polite formality. Otherwise there's not a great difference, in my opinion of common usage. (Except for 'giving thanks', but that's a whole other kettle of fish.)

  • 4
    "Thank you" is appropriate for formal situations. In formal situations "Thanks" comes across as a flippant remark.
    – oosterwal
    Commented Jul 26, 2011 at 4:06
  • I think that "Thank you" is not exclusively for formal situations. The original question acknowledged that ‘thanks’ is slightly more informal than ‘thank you’.
    – Richard A
    Commented Jul 26, 2011 at 8:24

I feel Thanks is just fulfilling an obligation to be grateful whereas Thank you is a sincere appreciation of what has been done.