18 Other Ways to Say For a Long Time (With Examples)

“For a long time” does the job, but it says the same thing in every sentence, and English is full of sharper ways to stretch a moment out. Alternatives like “for ages,” “for an extended period,” and “for donkey’s years” let you match the timescale to the tone, from a formal report to a chat with an old friend. This guide gives you 18 alternatives across everyday, formal, and idiomatic phrases, each with a clear definition and an example sentence.

In this guide, you’ll find 18 handpicked alternatives to “for a long time,” each with a clear definition and an example sentence. Use them for essays, emails, stories, and everyday conversation alike. You can also explore the synonym finder on infospebble.com for even more word choices across dozens of topics.

In this guide

1. Everyday phrases
2. Formal and written phrases
3. Idiomatic and colourful phrases
4. Quick comparison: which phrase should you use?
5. Frequently Asked Questions

Everyday phrases

Use these in conversation and casual writing, they sound natural everywhere.

• 1. For ages, a very long time, said casually. We waited for ages before the bus finally came.
• 2. For a very long time, the plain, emphatic version of the original. She has lived in this city for a very long time.
• 3. For quite a while, a long but unspecified stretch. We haven’t seen each other for quite a while.
• 4. For a good while, a satisfyingly long stretch of time. He stood there for a good while, just watching the sea.
• 5. For hours on end, continuously for many hours. The children played for hours on end.
• 6. For an eternity, an exaggerated way to say it felt endless. The meeting dragged on for an eternity.

Formal and written phrases

These belong in reports, essays, and professional emails.

• 7. For an extended period, a longer-than-usual stretch, stated neutrally. The bridge will be closed for an extended period.
• 8. For a prolonged period, a long period, often longer than expected. The patient was kept under observation for a prolonged period.
• 9. For a considerable length of time, a notably long duration, formal and precise. She worked on the project for a considerable length of time.
• 10. Over an extended period, spread across a long stretch rather than all at once. The changes took effect over an extended period.
• 11. For a lengthy stretch, a long, unbroken run of time. The team went without a win for a lengthy stretch.
• 12. For a significant period, a long period that matters or is worth noting. He was absent from work for a significant period.

Idiomatic and colourful phrases

These add humour and personality, best for informal writing and storytelling.

• 13. For donkey’s years, British slang for a very long time. They’ve known each other for donkey’s years.
• 14. For yonks, informal slang for ages. I haven’t been to the cinema for yonks.
• 15. Since forever, an exaggeration meaning as long as anyone can remember. We’ve been friends since forever.
• 16. For aeons, literally ages of geological time, used for comic effect. I’ve been waiting for aeons for this parcel.
• 17. For a month of Sundays, a very long time, with old-fashioned charm. It took a month of Sundays to finish the renovation.
• 18. Till the cows come home, indefinitely, for as long as it takes. You can argue till the cows come home, but the decision stands.

Quick comparison: which phrase should you use?

Frequently Asked Questions

What is the most formal way to say “for a long time”?

“For an extended period” and “for a considerable length of time” are the safest formal choices. The Cambridge Dictionary entry for “ages” defines it as a very long time, the casual cousin of the formal phrases above.

Is “for ages” too informal for work emails?

For internal chats it is fine, but for clients or formal reports use “for an extended period” instead. Tone should match the reader, not just the meaning.

What is the difference between “for a while” and “for quite a while”?

“For a while” can be short or long; “for quite a while” clearly means a long stretch. Adding “quite” stretches the time. For more time expressions, see our other ways to say “after a while”.

Can I use “for donkey’s years” in American English?

Americans will usually understand it, but it is distinctly British. In the US, “for ages” or “since forever” lands more naturally.

What should I use in an essay instead of repeating “for a long time”?

Rotate through “for an extended period,” “over a long period,” and “for a significant period.” Variety keeps academic writing readable. For phrases about the distant past, see our other ways to say “a long time ago”.

Is “till the cows come home” about waiting or arguing?

Both, it means “for an indefinitely long time,” so it fits waiting, arguing, or debating. It is always humorous, never formal. For words about doing two things at once, see our other ways to say “at the same time”.

Final Thoughts

The right way to say “for a long time” depends on who is reading and how formal the piece is. Use “for an extended period” for reports, “for ages” for everyday chat, and “for donkey’s years” when you want a laugh. Whatever you choose, match the timescale to the tone, a vivid idiom in a formal report reads as careless, and a stiff phrase in a friendly text reads as cold. And when the long stretch lies in the past, our other ways to say “a long time ago” covers the backward-looking phrases that follow.