Best time to send cold email and how to test it on your list

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Picture a sales team in New York firing off every cold email at 9 am sharp, their own time zone, no exceptions. Half their list is in London, already at lunch. The other half is in San Francisco, still asleep. Same send button, three different inbox realities.

I’ve pulled the data on this because every team asks the same question: what’s the best time to send cold email. The honest answer is that timing is a small lever, and it’s an easy one to get right once you stop guessing and start testing on your own list.

In this article, I’ll show you how much send time actually moves reply rates, why there’s no single magic hour or day that works for everyone, and what lemlist’s own data says about reaction speed and step spacing instead. I’ll also give you a sending setup you can copy and a simple test plan to find the window that works for your audience, not someone else’s benchmark.

How much send time really matters

The best time to send a cold email is during the recipient’s local working hours. That single adjustment puts your message at the top of the inbox when they sit down to work, instead of burying it under overnight noise.

That said, timing is a small lever. Your targeting, your offer, and your cold emailing copy carry most of the weight. According to lemlist internal data, the average email reply rate across lemlist campaigns is 2.72%, and the median campaign sits at 1.13%. Moving the send hour around will not double those numbers. Picking the right accounts and writing a relevant first line will.

Think of send time as the last five percent. Get it wrong and you lose easy replies. Get it right and you stop leaving money on the table.

Why there is no universal best day or hour

Most “best time” articles pull their recommendations from open rate data, which are unreliable. We cover why in detail below.

The right send window depends on your audience, their role, and their market. A CFO in London and a marketing director in Austin check email at different hours, on different days, with different inbox habits.

We looked at reply rates across every market in the lemlist dataset. lemlist internal data shows reply rates move within one point across the year, with no summer or December drop. Waiting for a “better month” to launch your campaign costs pipeline without giving you anything back.

lemlist data does not rank one weekday or hour above another for email. Anyone handing you a single magic slot is probably reading cold email open rates, which are unreliable for the reasons we cover below.

The timing that moves replies

If the send hour is a small lever, reaction speed is a big one.

lemlist internal data shows that when a prospect replies, it is usually within two days of the first message and after about two touches. That means the gap between your steps matters more than whether you clicked “send” at 8:47 am or 9:12 am.

In the US, follow-ups spaced one day apart reply at 3.63%, compared to 2.98% for two to three day spacing according to lemlist internal data. Tighter spacing keeps you top of mind while the problem you mentioned is still fresh.

The biggest timing effect we see is signal speed. lemlist internal data shows that leads added by a buying signal and contacted the same day reply at 21.3%. Wait a week and that drops to 8.1%. The moment a prospect raises their hand, the clock starts. Your send hour is secondary to how fast you act on that trigger.

Line up email steps with call windows

Cold email rarely works alone. Most sequences include a call step, and the timing of that call step should drive the timing of the email before it.

lemlist internal data shows calls connect best Tuesday to Thursday, with 10 to 11 am and 2 to 3 pm local time as the strongest slots. Friday is the weakest day in every market.

If your sequence sends an email on day 1 and a call on day 2, schedule the email so the call step lands on a Tuesday, Wednesday, or Thursday morning. Sending the first email on a Monday morning sets up a Tuesday call. Sending it on a Thursday afternoon sets up a Friday call, which is the worst window you could pick.

Plan your sequence calendar backward from the call. You can read more about call timing in our best time to cold call guide.

Send in the recipient’s time zone

If your list spans multiple time zones, sending at 9 am in your own time zone means some leads get your email at 6 am and others at noon. Neither is ideal.

Send in the recipient’s local time zone instead. When a lead’s location is known, their email arrives during their working hours. When it is unknown, set a fallback time zone that covers the majority of your list. If 70% of your leads are on the US East Coast, use Eastern as the fallback.

Pacing matters too. If you import 500 leads at once and they all share a time zone, you do not want 500 emails firing in the same minute. Space new leads out so your sending pattern looks human and your mailbox stays healthy. A gap of 15 to 20 minutes between new leads keeps volume steady without tripping spam filters.

When to send follow-ups

Space the first steps close together. lemlist internal data shows that one day gaps outperform two to three day gaps in the US, and that most replies come within two days of the first message.

Here is a sample sequence that puts those findings to work:

Notice the send hour varies across steps. If every email arrives at the same minute each day, it looks automated. Shifting the hour by 60 to 90 minutes between steps makes the cadence feel more natural.

Judge a campaign after its first week. By then, most leads who will reply to the opening steps have replied. If the numbers are flat, change the copy or the audience before you change the clock. For more on follow-up cadence, see how many cold email follow-ups to send.

Why open rates are a poor guide to timing

Apple Mail Privacy Protection pre-loads tracking pixels for every email, whether the recipient reads it or not. Microsoft and Google security scanners do the same on corporate accounts. The result: your open rate is a blend of real readers and bots, and you cannot tell which is which.

If you optimize your send time for the highest open rate, you may be optimizing for the hour when the most security scanners run. That is a waste of a test cycle.

Judge timing by reply rate instead. Replies are real. A human typed a response and hit send. That is the signal worth chasing. For a deeper breakdown, read our guide on cold email open rates.

How to find your own best send time

Generic benchmarks tell you what works on average. Your list is not average. Here is a simple test plan to find your own best window.

Rules for a clean test

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  Change one variable at a time, day or hour, never both

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  Use the same copy and the same audience segment for both variants

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  Send enough volume per variant to trust the result (at least 100 leads per side)

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  Decide the winner on reply rate, never open rate

Run one test per cycle. Log every test so you build institutional knowledge instead of re-running the same experiment next quarter.

Keep your daily volume within safe limits for your mailboxes. If you need guidance on volume, check how many emails you can send a day. And for a deeper look at structuring tests, see our guide on cold email A/B testing.

How to schedule cold emails in lemlist

lemlist gives you direct control over when each email goes out.

Set sending days and hours. Open your campaign, go to Settings, then Schedules & launch. Choose the weekdays and the sending window (for example, Monday to Friday, 9 am to 5 pm). Set the pacing interval (“Reach a new lead every X minutes”) so leads enter the sequence at a steady pace instead of all at once.

Turn on timezone-based sending. In the same schedule settings, enable the timezone-based schedule. lemlist will send each email in the lead’s local time zone. If a lead has no time zone value, lemlist uses the fallback time zone you set. This means a lead in Berlin gets your email during Berlin working hours, and a lead in Chicago gets it during Chicago working hours, from the same campaign.

A/B test a step or a whole sequence. Open the step you want to test, click the three-dot menu, and select A/B test this step. lemlist creates two variants and splits leads between them. Compare reply rates to pick the winner. You can also A/B test an entire sequence to compare two different cadences or send windows side by side.

Disable open tracking. If you are judging timing by replies (and you should be), go to Settings, then Tracking, and toggle off open tracking. This removes the tracking pixel, which improves deliverability and keeps your data clean.

Final takeaway

The best time to send a cold email is during the recipient’s local working hours, and the best timing habit is reacting fast when a signal fires. Skip the search for a universal magic hour. Test days and step spacing on your own list, judge by replies, and let the data from your audience guide the schedule.

Build your first signal-based sequence in lemlist.