We are offering prices on some subscriptions which are normally priced for a full year, but allow users to buy only a few months worth.

We're calling these pro rata prices and talking about the prices being pro rataed or pro rated (depending on how we want to pronounce it) — is this good English? What would be a better way?

3 Answers 3


Can pro rata be used as a verb? And what should the past tense be?

The verb form would be prorate or pro rate. The past tense is prorated.

We're calling these pro rata prices and talking about the prices being pro rataed - is this good english? What would be a better way?

Yes, except you would refer to the prices as pro-rated. The second a gets dropped.


If you must, I would prefer pro rated or pro-rated rather than pro rataed, which looks as if it has fallen down a hole between Latin and English and is still showing its scars.


The phrase 'Pro Rata' derives from Latin. Therefore you cannot tamper with either form or spelling (For example: 'ad hoc'; 'modus operandi').

You cannot just use it as a verb, and the word 'prorated' is definitely wrong.

  • The OED disagrees with you (though it does say 'chiefly U.S.'). Sep 20, 2012 at 14:37
  • This is a tad too strong. I could just as confidently say that every word in English can be used as a verb. And every single word in this answer derives from another language (including Latin), yet you don't seem to have qualms tampering with their form and spelling.
    – RegDwigнt
    Sep 21, 2012 at 10:37
  • 2
    The OED has all sorts of examples of ad hoc having been "tampered with": ad hocness; ad hocing, ad hoc'ing, ad hoc-ing, ad hoccing, ad hocking; ad hoced, ad hoc'ed, ad hoc'd, ad hoc-ed, ad hocced, ad hocked; ad hoccism, ad hoc-ism, ad-hoc-ism, adhoc-ism, ad hocism, ad-hocism, adhocism, ad hockism, ad-hockism, adhockism; ad-hoc-ery, ad hoccery, ad- hoccery, adhoccery, ad hoc-ery, adhoc-ery, ad hocery, ad-hocery, adhocery, ad hockery, ad-hockery, adhockery; ad hocracy, ad-hocracy, adhocracy. The oldest from 1899.
    – Hugo
    Sep 22, 2012 at 6:45
  • 1
    This answer can be improved by citing a reputable reference which upholds your claim. As it stands, your answer could be taken as a pure statement of opinion and is liable to be downvoted or deleted.
    – MetaEd
    Sep 26, 2012 at 4:09

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