Best Time to Send Cold Email: What the B2B Data Actually Shows

The best time to send a cold email is a weekday morning in the recipient's local time, roughly 8 to 11 AM, with Tuesday to Thursday slightly ahead of Monday and Friday. That is where the larger published cold email datasets agree. They also agree that the difference between good and average slots is small, a few hundredths of a percentage point of reply rate, so the time you send matters far less than who you send to and what you say.

There is also a deliverability reason not to take "best time" literally. Pushing your whole day's volume out at 9:00 sharp creates exactly the kind of burst that Gmail tells senders to avoid. The second half of this post covers how to hit the right window without spiking.

What the cold email studies say

Only a handful of cold email datasets publish day or hour breakdowns, and they measure different things. We read each page below in October 2026 and quote only figures that appear on it.

Source	Sample stated	Time zone basis	Best day	Best time
Belkins, best time to send B2B emails (2026)	7.5 million cold emails, January to November 2025	Send time; recipient vs sender time zone not stated	Wednesday and Thursday, 0.48% reply rate	8 AM to 12 PM, 0.54% reply rate
Saleshandy, cold email statistics	30.31 million cold emails (page title)	Prospect's local time	Tuesday to Thursday	Tuesday 9 to 10 AM; 8 to 10 AM in the US and UK
Instantly, Cold Email Benchmark Report 2026	"Billions of cold email interactions", 1 January to 18 December 2025	Not stated	Wednesday highest; Tuesday and Wednesday peak	No hour-level data
Amplemarket, best time to send cold emails	"More than 200,000 leads"	Prospect's local time	Replies higher on Monday and Wednesday	Replies 7:30 to 8:30 AM; opens peak 5:30 to 6:30 PM
Danish Lead Co., best day to send cold email	1,612,521 emails across 465 campaigns, 90 days	Not stated	Wednesday, 1.18%	No hour-level data

Five sources, three of which publish numbers, and the numbers are small. Here is what each one adds.

Belkins: mornings win, weekdays are close

Belkins publishes the most complete breakdown, with reply and meeting rates by both day and time window. Its reply rate is replies divided by total emails sent, and the page notes this replaced the opens-based denominator of its 2023 edition, so the figures read lower than older versions.

Day	Reply rate	Meeting rate
Monday	0.45%	0.2%
Tuesday	0.45%	0.2%
Wednesday	0.48%	0.1%
Thursday	0.48%	0.2%
Friday	0.44%	0.2%
Saturday	0.35%	0.2%
Sunday	0.57%	Not reported

By time window, morning (8 AM to 12 PM) led at 0.54%, early morning (5 to 8 AM) followed at 0.52%, and afternoon (12 to 5 PM) was 0.47%. Both morning windows also had the highest meeting rate, 0.4%, against 0.1% for every other window.

Two details matter. Sunday's 0.57% comes from what Belkins calls "extremely low" volume, and the page describes Sunday sending as a niche approach, not a general recommendation. And the gap between the best weekday and the worst is 0.04 percentage points. Belkins' own conclusion is the right one: "Consistency across the week matters more than chasing a single best day."

One caveat on the hours: the page says its time-of-day data "reflects the time the email was sent, not the time it was received or read", and notes that for audiences spread across time zones the recipient's local time may differ. It does not say plainly which clock the windows use.

Saleshandy: Tuesday morning, local time

Saleshandy's report is the clearest on time zone, and it is the only one to split results by region. It states that "Tuesday between 9 and 10 AM in the prospect's local timezone consistently generated the highest reply rates", that Tuesday to Thursday outperformed the rest of the week, and that Monday mornings and Friday afternoons were weakest.

Two findings are more useful than the headline. In the US and UK, 8 to 10 AM local time produced the highest reply rates, but "across APAC markets, afternoon sends consistently outperformed morning sends." And "sending in the prospect's local timezone performed better than using a single global sending schedule."

The page gives rankings, not percentages, for the timing section, and it does not say whether the timing comparison uses all replies or positive replies. Its methodology section also gives two different date ranges for the dataset. Treat the direction as useful and the precision as unknown.

Instantly: Wednesday, and Friday's out-of-office problem

Instantly's 2026 benchmark report names Wednesday as its best day but publishes no per-day rates and no hour-level data. The report says "Tuesday-Wednesday see peak reply rates, Wednesday is highest", that Monday has the highest send volume on the platform, and that Friday brings the most auto-replies.

That last point is worth noting if your tool counts out-of-office messages as replies. A Friday send can look better than it is for the wrong reason. Our reply rate benchmarks post explains why automatic replies should be removed before you compare anything.

Amplemarket: opened in the evening, answered in the morning

Amplemarket's analysis is the only one that separates when people open from when they reply. Measured in the prospect's time zone, opens peaked on Wednesday and Thursday "between 5:30 PM and 6:30 PM", while replies were more likely "between 7:30 AM and 8:30 AM, especially on Mondays and Wednesdays."

The pattern is plausible: people triage their inbox at the end of the day and answer the next morning. But the page publishes charts only, with no rates and no period, so it is a pattern to test, not a number to plan around.

Danish Lead Co.: the weekend trap in miniature

This smaller dataset shows clearly why weekend figures in any study need care. Weekday reply rates sit in a tight band, from 0.99% on Monday to 1.18% on Wednesday. Sunday shows 19.36%, but that comes from 470 sends against more than 295,000 on every weekday. The page also counts out-of-office notices and unsubscribe requests as replies, which inflates every number. The weekday ordering is still informative; the Sunday figure is not.

Sources we left out

Several popular figures could not be checked. A widely quoted lemlist reply rate for 5 to 8 AM sends returned a 404 when we tried to read the original page, so it is not in the table. QuickMail's timing page publishes each day's share of weekly opens and replies, not a rate per email, with no sample size or period, so it can't be compared with the studies above.

Why newsletter studies give a different answer

Studies of marketing email measure a different audience, a different action and a different metric, so their "best time" does not carry over to cold outreach. MailerLite's best time to send email study, which is one of the most cited, is a good example. It covers 2,138,817 marketing campaigns sent through MailerLite between December 2024 and November 2025 in the US, UK, Australia and Canada. Its best day for opens was Friday, at 49.72%, and its best single slot was Friday at 6 PM.

That is a sound finding for newsletters and a poor guide for cold email, for three reasons.

	Marketing email (MailerLite)	Cold email (Belkins, Saleshandy)
Who receives it	Subscribers who opted in	People at work who did not ask
Success metric	Opens and clicks	Replies and meetings
Where it is read	Often on a phone, after hours	Usually during the working day
Best slot found	Friday 6 PM	Weekday mornings, recipient's time

First, the action is different. A newsletter succeeds when someone opens it and clicks a link, which people happily do on a Friday evening. A cold email succeeds when a professional replies to a stranger about work, which mostly happens during work hours.

Second, the metric is different. MailerLite itself notes that Apple Mail Privacy Protection affects open tracking and suggests testing on clicks instead. Cold email studies moved to replies for the same reason; Belkins says its switch followed the discontinuation of pixel-based open tracking. A study ranked by opens tells you when images were loaded, not when people read. More on that in what open rates can and can't tell you.

Third, the relationship is different. A subscriber expects the newsletter and recognises the sender. A cold prospect is deciding in a few seconds whether you are worth a reply, and they make that call when they are at their desk with the problem you mention in front of them.

Use the recipient's time zone, not yours

Every study that states its time zone basis measures in the prospect's local time, and Saleshandy found that doing so beat a single global schedule. A 9 AM send from London lands at 4 AM in New York and 1 AM in San Francisco, which puts it under a night's worth of other mail by the time anyone looks.

In practice:

1. Store a time zone on every contact. Derive it from the company's address, the prospect's stated location or the phone area code. A country field alone is not enough for the US, Canada or Australia.
2. Schedule by contact time zone, not campaign time zone. Most cold email tools have a setting for this. Check it is switched on, because the default is often the account's own zone.
3. Group sends into regional campaigns if your tool cannot schedule per contact: one for the Americas, one for Europe, one for Asia-Pacific.
4. Don't copy US and UK timing to APAC. Saleshandy's finding that afternoon sends did better there is a reason to test regions separately.

The deliverability reason not to send at one hour

Even if 9 AM were provably best, sending everything at 9 AM would be a mistake, because mailbox providers read sudden bursts as a risk signal. Google's sender guidelines are direct about it: "Send email at a consistent rate. Avoid sending email in bursts." The same page warns that "immediately doubling previously sent volumes suddenly could result in rate limiting or reputation drops."

What that rate limiting looks like is listed in Google's SMTP error reference. The 421 4.7.28 family covers cases where "Gmail has detected an unusual rate of email", including from your IP, your DKIM domain or a URL domain in your messages. Several 421 4.7.0 responses mean low IP or domain reputation, with the message deferred. These are temporary failures, and the background is in our page on 421 4.7.0. Your server retries, the mail usually arrives later, and the "perfect" send time is lost anyway.

Yahoo's SMTP error codes page lists "unusual traffic patterns from your sending server's IP address" among the causes of its 421 and 451 deferrals. On the sending side, Microsoft's Exchange Online limits cap each mailbox at 30 messages per minute, and "any excess in message submission will be throttled and successively carried over to the following minutes." A burst from a Microsoft 365 mailbox does not even leave at the time you chose.

There is a simpler reason too. A spike of identical messages from one domain within a few minutes is what bulk mail looks like. Cold email that spreads across a two- or three-hour window, with a few minutes between sends from each inbox, looks more like a person working through their list.

So aim at a window, not a minute:

• Use a window of two to three hours, such as 8 to 11 AM recipient time, and let the tool space sends randomly within it.
• Keep a gap between sends from each mailbox. Most tools let you set a minimum and random delay. Several minutes is common.
• Keep daily volume steady across the week rather than loading Tuesday because a study said so. Our post on cold emails per day per inbox covers how to size that number, and inbox rotation covers spreading it across mailboxes.
• Ramp new domains and mailboxes gradually. A warm-up schedule matters more than any send time.

Timing for follow-ups

Follow-ups should land in the same recipient-time window as the first email, a few days apart. Instantly's best time to send cold email post says its benchmark recommends spacing touches "around 3–4 days apart." If the first email went on a Tuesday morning, a follow-up the following Friday or Monday morning keeps the rhythm without crowding the inbox.

Avoid scheduling the last step of a sequence on a Friday afternoon, which Saleshandy flags as one of the weakest slots ("Don't send cold emails after Friday 2 PM"). For how many steps to use, see how many follow-ups a cold email sequence should have.

How to find your own best time

Published studies give you a default. Your own data, measured properly, should replace it within a few campaigns.

1. Start with the consensus window: Tuesday to Thursday, 8 to 11 AM in the recipient's time zone, spread evenly, with Monday and Friday at normal volume rather than off.
2. Test one variable at a time. Split a single list randomly into two halves and change only the window, for example 8 to 10 AM against 1 to 3 PM.
3. Measure human replies per delivered prospect, with auto-replies removed. Opens are not reliable enough to judge timing.
4. Wait for enough data. At reply rates under 1%, a few hundred sends per arm will not separate a real difference from noise. Several thousand per arm, or several campaigns pooled, is more realistic.
5. Segment by region and role. Founders, finance teams and field-based roles keep different hours.

Fix the list before the clock

Bounces cost more reply rate than a bad send time does. A dead address cannot reply at any hour, and every hard bounce counts against your sender reputation whether it went out at 9 AM or 3 PM. The gap between the best and worst weekday in Belkins' data is 0.04 percentage points; a list with a few per cent invalid addresses does far more damage than that. The reasons lists decay are in why cold emails bounce.

Before you tune timing, check the list. You can test a sample with the free email verifier or run a whole file through the free list health check and verify the mailboxes on the paid plan, then spend your testing effort on the window that suits your prospects.