TOEIC Decision Point

Until vs By: Choose by Continuing Time or Deadline

In Part 5-style sentences, until and by can both connect an action or state to a time. The key is whether the sentence shows continuation up to that point or a latest completion time.

Man writing at a desk beside a laptop and papers at night

The practical choice is not “Can I explain the grammar?” It is: does the sentence show something continuing, or does it show a deadline?

Until = continues up to a time. By = no later than a time.

The decision check

Do not translate the sentence first. Look at the action or state around the time expression.

Until

Use it when something continues up to a time: open until 6 p.m., available until Friday, wait until the manager returns.

By

Use it when something must happen no later than a time: submit by Monday, arrive by 3 p.m., complete by the deadline.

The signal to remember

Until = keep going up to the point. By = complete no later than the point.

This is the MTC move. Check whether the action/state continues or whether the time is the latest permitted point for completion.

The office will remain open until 7 p.m.
The office stays open up to that time. Choose until.
Please submit the report by 7 p.m.
The report must be submitted no later than that time. Choose by.
The discount is available until the end of June.
The discount continues up to that point. Choose until.
All applications must be received by the end of June.
The applications must arrive no later than that point. Choose by.

What Part 5-style practice asks you to notice

Business-style grammar sentences can use this contrast with offices, stores, delivery schedules, application forms, reports, payments, meetings and service periods.

Both choices connect to time, but the grammatical relationship is different: until marks continuation up to a point, while by marks the latest time for an event or completion.

open until / available until / valid until / wait until
Something continues up to a time. Choose until.
closed until / unavailable until / postponed until
The condition continues up to a time. Choose until.
submit by / finish by / arrive by / pay by
The time is the latest permitted point. Choose by.
be completed by / be received by / be returned by
The time is a deadline. Choose by.

Watch the small words

The action near the blank usually makes the intended time relationship clear.

Choose until

Look for continuing states or actions: open, available, valid, closed, postponed, wait, remain, stay.

Choose by

Look for completion or arrival points: submit, finish, complete, receive, return, pay, arrive, send.

This is not about explaining the whole sentence. It is about seeing whether the time marks continuation or a latest completion point.

Quick TOEIC check

Choose first. Then read the source feedback. Use the same decision each time: continuation, or deadline?

Context: The desk is already open and closes at 8 p.m.; the blank must mark how long that continuing state lasts.

1. The customer service desk will be open ___ 8 p.m.

Context: 8 p.m. is the latest permitted submission time; the form may be submitted earlier.

2. Please submit the completed form ___ 8 p.m.

Context: The offer is already valid and stops being valid when Friday arrives; the blank must mark the end of that continuing state.

3. The special offer is valid ___ Friday.

Context: Friday is the latest payment date; each invoice may be paid earlier.

4. All invoices must be paid ___ Friday.

The mistake fast readers make

Fast readers can see a time expression and choose by translation alone. That can hide the difference between duration and deadline.

Weak choice

Choose because both words seem connected to time.

Better choice

Check the action or state. Does it continue, or must something happen by a latest time?

This is the MTC move: avoid the grammar maze, find the signal, make the decision and move on.

Why this mistake returns under pressure

If you know until and by during review but still miss them in timed practice, the problem may not be the meanings alone. It may be your decision pattern.

Under pressure, use the same move every time: look at the action around the time and ask whether it continues or whether the time is a deadline.

Decision tool: continues up to the point = until. No later than the point = by.
Next step

Use small TOEIC mistakes as a diagnostic

If you know the answer after review but miss it during timed practice, the problem may not be the word alone. It may be your decision pattern.

Start with the Learning Block Diagnostic to explore whether repeated mistakes connect to Speed Trap, Memoriser, Over Thinker, Translator, Passive Listener or Burnout. One missed item alone is not enough evidence to identify a Learning Block.

Take the Learning Block Diagnostic Read During vs While Find Your TOEIC Plan

Continue reading

Use these pages to turn small TOEIC mistakes into clearer decisions and better review.

Back to top Grammar Drills Learning Block Diagnostic TOEIC Plan Finder Part 5 Guide Despite vs Although Because vs Because Of
FAQ (English) — Until vs By (No numbering, UTF-8 clean, formatted for SEO + chatbot) What is the difference between “until” and “by” in TOEIC questions “Until” means something continues up to a point in time. “By” means something is finished before or at that time. When should I use “by” instead of “until” in TOEIC grammar Use “by” when the sentence is about a deadline or goal — something that must be completed before or at a specific time. Why is “until” the wrong choice in deadline questions “Until” suggests ongoing action. For deadlines, you need “by” to show completion. How do I know if TOEIC wants “until” or “by” Ask: is the action continuing (use “until”) or finishing (use “by”)? That’s the key test. Is “by” used for future deadlines on TOEIC Yes. “By” is the standard preposition to mark future deadlines in TOEIC questions. Does “until” mean the same as “before” No. “Until” shows something continues up to a time. “Before” and “by” show when something is done. What does “by Friday” really mean on TOEIC It means the action should be completed any time before or on Friday — not after. Can “until” be used in TOEIC Part 5 questions Yes, but only when the verb shows a continuous action like “wait,” “stay,” or “work.” Is “until” ever correct in TOEIC deadline questions Rarely. “Until” only fits if the sentence is about continuing, not finishing. What is the grammar logic behind “until” and “by” “Until” = continuous action. “By” = finished action. TOEIC tests this subtle difference often. What kind of verbs follow “by” in TOEIC traps Verbs like “complete,” “submit,” “finish,” “respond,” or “send” often go with “by” in deadlines. How does TOEIC test time prepositions like “by” and “until” TOEIC puts both as answer choices and hides the trap in the logic of the verb. Does “stay until” mean the same as “stay by” No. “Stay until” is correct. “Stay by” is incorrect and unnatural. Can I use “by” when something continues up to a time No. Use “until” when describing something that keeps going up to a certain point. Why do I keep getting “by” vs “until” questions wrong Most people follow feeling, not logic. These questions test meaning, not memory. What is the difference between “stay until” and “leave by” “Stay until” means you are present up to that time. “Leave by” means you are gone before or at that time. Are “until” and “by” tested in TOEIC Part 6 fill-in-the-blank Yes. TOEIC often uses short time-based sentences to test this difference under time pressure. What’s the trick for choosing between “until” and “by” Check if the sentence is about continuing (until) or completing (by). That’s the only thing that matters. How can I practice the “until” vs “by” question type Review real TOEIC-style questions where the action verb tells you the right preposition. Which one is correct: submit until Friday or submit by Friday “Submit by Friday” is correct. “Submit until Friday” is incorrect because “submit” is a completed action.