Possible Duplicate:
Does “notified by [date]” include the end date?
“I will do it by Monday”. Does it mean before the beginning or before the end of Monday?

If something has to be finished "by spring 2013," how long do I have?

Does this imply the beginning, or the end of spring?

  • Please edit the question to cite references consulted and your own research results. Questions lacking evidence of research effort are incomplete.
    – MetaEd
    Dec 31, 2012 at 8:12

5 Answers 5


The answer to your question is that it implies nothing and neither.

You cannot know for sure without getting explicit confirmation. People will twist things to their own advantage each and every time. The only prudent course is to assume the worst case.

If I expect something to be done by next week, then when next week rolls around, it had best be done already. That means by the start of the week. However, the person whom I’ve directed to do it will naturally want to dillydally and delay until the end of the week. No joy will be found here on either side.

Don’t guess: get it in writing, and get it in UTC. For example, next year’s vernal equinox occurs on March 20th of 2013 at 11:02 UTC. That is an exact time. Find out if that is when they expect it done. If they say no, make them tell you when. Exactly when.

  • At the start or the end of 11:02 UTC? For God's sake, man, be specific.
    – MetaEd
    Dec 31, 2012 at 8:11
  • Is MετάEd Vulcan for Spock? Dec 31, 2012 at 9:16
  • tchrist: is it OK if I add your post to my personal 'killer quotes' book (under 'obscurantism')? Dec 31, 2012 at 9:19
  • @EdwinAshworth Aye.
    – tchrist
    Dec 31, 2012 at 13:09

It could mean either, but generally the 'by' is taken to mean 'by the start of'

Of course the correct solution is to ask for whoever gave you that timescale to be more precise :-)

  • I disagree that "by" generally means "by the start of." If you say that you'll have something to me "by Saturday," I wouldn't think that meant by one minute after midnight on Friday, or even by Saturday morning, I assume you meant "before the end of the day on Saturday." I think "by" is perhaps even more likely to mean "by the end of."
    – J.R.
    Dec 31, 2012 at 1:05
  • Interesting - I would expect it by start of Saturday every time.
    – Rory Alsop
    Dec 31, 2012 at 1:06
  • 1
    Well, then, your solution for more precise language appears to be the right one. :^)
    – J.R.
    Dec 31, 2012 at 1:07

It depends a lot on what the context is. I think the other two answerers are right in suggesting that you need to ask more specifically what this means.

If the context is something in a university, then "by spring 2013" normally means

by the end of the spring semester.

which often means

by the last day of class.

But usually in all such cases, either (a) there isn't a hard deadline, or (b) it's specified more clearly elsewhere.


My authors present me with the problem quite frequently. There are on basic ways of saying this:

"Can you finish this by Friday?
"Can you finish this before Friday?
"Can you finish this on Friday?
"Can you finish this no later than 5 p.m. on Friday?

I usually assume that the first two mean the same thing: no later than 2400 hours on Thursday, but, if I'm swamped with work and late, I'll rationalize that the first gives me until 2400 hours on Friday, and that the third and fourth really do mean Friday.


That would imply neither. The sentence by itself sounds ambiguous and can imply the start, end, or some time the middle of the spring. Here at school, our professors usually tell us by Friday midnight or by Friday before 12:00 AM, which means that any submission after 12:00 AM will not be accepted.

  • One really should not say 12 am; noon is much better — presuming that that is what was meant. Also, Friday midnight is unclear as well, because one does not know whether it is the one that starts Friday or the one that ends it.
    – tchrist
    Dec 31, 2012 at 5:56

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