Since vs For in Work Emails: Say When and How Long

Use since for a starting point and for for a duration. “Since 1 November” answers when a period began. “For three weeks” answers how long it has lasted. In a work update, also make clear whether the activity is still happening.

This lesson focuses on those time meanings. It does not cover other uses, such as since meaning because. The people and workplace details below are fictional.

Start with the time information the reader needs

Compare these two descriptions of an ongoing trial:

• Starting point: The trial has been running since 1 November 2026.
• Duration: The trial has been running for three weeks.

The first locates the beginning. The second gives the elapsed length. BBC Learning English’s lesson on for and since explains this distinction and contrasts continuing situations with finished ones.

Choose the information that answers the reader’s question. If someone asks how long a trial has been running, a duration gives a direct answer. If they need its exact starting date for a briefing, give the date. You do not have to include both every time.

For does not mean the work is still happening

Compare:

The trial has been running for three weeks. It is still underway.

The trial ran for two weeks. It ended on 15 November.

Both use for to express a duration. The verb and the surrounding information describe different states of the work. Do not decide whether something continues just by looking for for or since.

Here, the continuing form describes a trial that is explicitly still running; the past simple describes one that has explicitly ended. The British Council’s present-perfect guide also covers other uses of the tense. These examples are not a rule that every present-perfect sentence describes an activity continuing now.

Practice: report how long a trial has been running

You are Maya, coordinating a trial of a reception checklist. Omar is preparing an internal briefing. He asks how long the trial has been running and whether it is still underway.

Use these facts:

• You are writing on 22 November 2026.
• The trial began on 1 November 2026 and is still running.
• Three weeks have elapsed. The checklist is used during normal work.
• You have not been given results, an evaluation, an expansion decision or an ending date.

Write a subject and a short reply before reading the example. Answer Omar’s question about duration and current status. You do not need to add a request, attachment or promise.

One possible reply

Subject: Reception checklist trial — duration and current status

Hi Omar,

The reception checklist trial has been running for three weeks. It is still underway.

Best, Maya

“For three weeks” supplies the length Omar asked about. “It is still underway” states the current status directly. This describes the trial’s duration, not uninterrupted work by the reception staff.

The reply does not say the checklist has improved anything or will be used permanently. Those conclusions would need information that this task does not provide.

If Omar needs the starting date instead

Change the main sentence to:

The reception checklist trial has been running since 1 November 2026.

That answers a different time question. Keep the status clear, but do not add a second duration sentence unless Omar needs it too.

A natural alternative is “The trial started on 1 November 2026 and is still underway.” You do not need to force since into a sentence when another clear construction does the job.

Revise it: the trial has already ended

Now change the facts before sending your email. The writing date is still 22 November 2026, but:

• The trial ran from 1 to 15 November 2026, a two-week period.
• It ended on 15 November and is not running now.
• You still have no information about its results or why it ended.

Rewrite the reply before reading the next example. Change the verb, replace the old three-week duration, and state that the trial ended. Merely replacing one preposition will not make the original message accurate.

One possible revised reply

Subject: Reception checklist trial — duration and current status

Hi Omar,

The reception checklist trial ran for two weeks, from 1 to 15 November 2026. It ended on 15 November and is no longer running.

Best, Maya

“Ran for two weeks” describes the finished period. The dates let Omar locate that period for his briefing, and the final sentence makes the present status explicit.

The revised facts replace the first exercise’s facts. This is not a correction to an email already sent, so an apology or “please disregard my previous email” would add a situation that did not happen.

Check what changed—and what remains unknown

Before comparing your reply with these answers, check:

1. Does “for two weeks” tell Omar that the trial succeeded?
2. Can you keep “has been running for three weeks” in this revised update?
3. Do you need to explain why the trial ended?

Answers: No to all three. Duration is not an outcome. The old wording conflicts with the new two-week, finished period. A reason has not been supplied, so leave it out rather than guessing.

Check the timeline before choosing the wording

For a short work update, identify the starting point, the elapsed length and the current status first. Then choose a sentence that preserves those facts. If the status changes, review the whole message for an obsolete duration, verb or conclusion.

For organizing a broader update, use the project status update email guide. For future completion times and continuing work, practice by versus until. The business email English guide also covers clear dates and useful editing habits.

To practice your own wording, start practicing for free. EmailBetter sends workplace scenarios tailored to your profile to your inbox. You write your reply in your usual email app, then review AI feedback in your dashboard.