I have data file containing titles like

Invoice #ZT-123456 June 2017


Agreement #1_ABCD Foo Services

but I need to put these titles into an app where character # is not allowed. (Edit: And U.S. customer will see what I wrote there.)

What is the best alternative writing when I cannot use #?

I was thinking about something like this:

Invoice Nr. ZT-123456


Invoice nr. ZT-123456

Maybe I could use number but replacing symbol with complete word does not seem appropriate to me in this context.

  • 1
    This is not an English question. Call it whatever you want. Commented Aug 17, 2017 at 15:10
  • 5
    "No." is the usual English abbreviation for "Number". Commented Aug 17, 2017 at 15:14
  • @MaxWilliams – I want this is to feel natural to U.S. customer. I am not sure if they will be happy if I call it any way I want.
    – miroxlav
    Commented Aug 17, 2017 at 15:19
  • If you're not under length restrictions, just spell it all out: "Invoice number".
    – Hellion
    Commented Aug 17, 2017 at 15:30
  • 3
    The Numero sign № (U+2116) can also be rendered as either No or N plus superscript 'o'. Also used is 'Nr' which I'm familiar with from use in Bills of Quantity where it has gradually taken over from № during the length of my career (going on 40 years) though I believe it is originally german. №t sure why it has changed, possibly more pan-european specification going on and it avoids the risk of laymen thinking it means 'none'.
    – Spagirl
    Commented Aug 17, 2017 at 15:32

1 Answer 1


The standard American English abbreviation for number is "No." (uppercase N, lowercase o, followed by a period). For example, Invoice No. 65967.

No., no. written abbreviation

number. room No.145

Source: Kernerman English Multilingual Dictionary © 2006-2013

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