Best time to send marketing emails: how to find yours
Short answer. There is no universal best day and time for every brand. For an ecommerce campaign, start with two time slots that fit how your customers shop, deliver in each recipient's local timezone, and compare clicks, conversions, and revenue per recipient. Behavior-triggered emails should follow the event rather than a generic weekday chart. Deadline-driven messages need enough time for the customer to act.
The question “What is the best time to send marketing emails?” often combines four separate decisions: campaign date, local delivery time, delay after an event, and the total message pressure each person receives. Optimizing only the hour can move opens without creating an additional sale.
This guide provides a method that works with Klaviyo, Brevo, or another ESP. Product capabilities were checked against official documentation on July 16, 2026.
A practical starting point by email type
| Message type | Reasonable starting point | What should actually decide it |
|---|---|---|
| Newsletter or editorial content | Two daytime slots in local time | Reading habits, B2B or B2C audience, content value |
| Promotional campaign | Before the expected shopping window | Offer duration, inventory, margin, and other channels |
| Product launch | Early enough to discover and return | Launch time, availability, and the full sequence |
| Checkout abandonment | Soon after abandonment, then longer delays | Intent, purchase cycle, and support needs |
| Post-purchase | Based on confirmation, shipping, and product use | Operational data and consumption moment |
| Replenishment | Before the likely runout date | Product-specific consumption interval |
| Winback | Around the expected reorder cycle | Cohort, last order, and churn risk |
| Transactional | As soon as the event requires | Reliability and latency, not marketing optimization |
This table is a hypothesis, not a rule. Coffee and furniture do not share a buying cycle. A webinar reminder should not be distributed over 24 hours when the event starts in one hour.
Why generic “best send time” studies mislead teams
They combine incompatible audiences
An industry average mixes countries, business models, messages, and list maturity. The best slot for a US B2B software company is not automatically useful for a French beauty brand.
They confuse opens with business results
Opens depend on deliverability, subject line, sender recognition, and privacy features. Apple Mail Privacy Protection can load remote content without proving that a person read the message. A time slot can win on opens and lose on clicks or revenue.
They ignore inbox competition
Popular send times attract more senders too. Inbox placement, reputation, and relevance can matter more than a 10-minute scheduling difference.
They freeze behavior that changes
Seasonality, holidays, work patterns, product categories, and lifecycle stage all affect engagement. A result should be retested instead of becoming a permanent rule.
Step 1: choose the metric before the time
Set one primary measure that matches the job of the message:
- commercial campaign: net revenue or contribution margin per recipient;
- editorial content: unique click rate and qualified site visits;
- activation: product action or first purchase;
- replenishment: category purchase within a defined window;
- event: registration and attendance, not just a click;
- deliverability: complaints, unsubscribes, and bounces as guardrails.
Do not switch the primary metric after seeing the outcome. If you inspect enough metrics, one will often look like a winner by chance. When behavior genuinely differs, the CRM segmentation guide helps define testable groups without splitting the database into noise.
Step 2: separate campaigns from flows
A campaign follows a scheduled commercial decision. A flow follows an individual event or state. Read Klaviyo flows versus campaigns before optimizing two different timing problems as if they were one.
Campaign timing
For a campaign, the variable is the delivery date and local time. Start with a difference large enough to interpret, such as morning versus late afternoon. Two slots 15 minutes apart rarely teach you anything useful.
Flow timing
For a flow, the key variable is usually the delay after a signal. Compare 30 minutes after Started Checkout with two hours after, not Tuesday with Thursday. Add exit filters so a purchase, refund, or support case stops messages that are no longer relevant.
Transactional timing
Do not delay an order confirmation or password reset to reach a supposed optimal hour. Speed and reliability are part of the message promise.
Step 3: deliver in the recipient's timezone
A campaign scheduled for 10 a.m. in Paris arrives at 4 a.m. in New York and in the evening across parts of Asia. Use the profile's timezone when it is reliable. Otherwise, segment by country or region and document the fallback.
Also verify:
- daylight saving time behavior;
- profiles with a missing country or timezone;
- when the ESP takes its audience snapshot;
- the cutoff time for an offer;
- customer-service coverage after delivery.
Klaviyo's official guide to campaign scheduling and send options explains recipient-local delivery and when recipients can be recalculated.
Step 4: design a clean send-time test
Keep everything else constant
Use the same eligible audience, content, subject line, offer, and measurement window. Randomly assign contacts to time slots. Exclude employees, seed profiles, people without consent, and contacts exposed to a competing campaign.
Use a meaningful sample
A test with 200 recipients cannot reliably separate two low conversion rates. If the audience is small, repeat the experiment across comparable campaigns and look for a consistent direction instead of naming a winner after one send.
Wait for the conversion window
Measure after a window that fits the purchase cycle, often 24 or 72 hours for a campaign and longer for considered purchases. Include refunds and margin when a promotion may attract low-quality orders.
Protect deliverability
A commercial winner should not create an unacceptable complaint or unsubscribe rate. Define guardrails before the test and stop a variant that creates a clear risk. The email deliverability guide provides the controls to monitor alongside the experiment.
Step 5: segment only where behavior supports it
Different schedules can make sense for:
- major countries or timezones;
- customers and prospects;
- B2B and B2C audiences;
- frequent buyers and new subscribers;
- categories used in the morning, during work, or in the evening.
Avoid building 20 rules on tiny samples. Start with a difference that has a behavioral reason, then add detail only when it produces a repeated gain.
When to use automated send-time optimization
Klaviyo Smart Send Time
Klaviyo uses exploratory and focused phases. Its official Smart Send Time guide says an eligible campaign must be able to reach at least 12,000 recipients. The exploratory phase distributes delivery across 24 hours in each person's local timezone, then the system validates a time slot.
This approach fits non-urgent campaigns. Klaviyo advises against using it around a strict deadline or a major date for the brand because distributed delivery can reach some contacts too late.
Brevo Send at best time
Brevo offers Send at best time for campaigns and automation emails. The feature uses engagement history and delivers within 24 hours of the selected date. Brevo recommends sending several campaigns first so the model has account-level engagement data.
Automated optimization does not replace message strategy. A product can optimize engagement while your actual objective is net revenue, registration before a deadline, or coordination with a launch.
A four-week test plan
| Week | Action | Decision |
|---|---|---|
| 1 | Establish a baseline by timezone and campaign type | Select two plausible slots |
| 2 | Run a randomized A/B test | Check data quality and guardrails |
| 3 | Repeat on a comparable campaign | Look for a consistent outcome |
| 4 | Roll out the better slot to part of the audience | Measure incremental value and document it |
Keep a log with the audience, date, timezone, slots, message, offer, incidents, primary metric, and outcome. Without a shared record, teams repeat the same debate every quarter.
Mistakes to avoid
- Picking Tuesday at 10 a.m. because a generic benchmark says so.
- Optimizing opens without reviewing clicks and conversions.
- Sending at the same clock time across timezones.
- Testing the hour, subject line, and offer at once.
- Calling a winner after one small campaign.
- Distributing a campaign when the offer expires quickly.
- Ignoring other campaigns, SMS, and flows received by the same person.
- Keeping one schedule all year without retesting.
FAQ about email send times
What is the best day to send a marketing email?
There is no universal best day. Start with two days that fit how your audience shops or works, then compare one business metric across several similar campaigns.
What is the best time to send a newsletter?
Test two meaningfully different slots in each recipient's local timezone, such as morning and late afternoon. Judge them on clicks and qualified visits, not opens alone.
Should you send marketing emails on weekends?
Yes, when customer behavior supports it. A leisure-focused B2C audience may engage on weekends, while a professional newsletter may perform better during the workweek. Test instead of assuming.
When should an abandoned-cart email be sent?
The delay should follow the behavior, not the calendar. Start with a first message reasonably close to abandonment, stop immediately after purchase, and test a shorter or longer delay based on the decision cycle.
Can AI choose the best send time for me?
It can personalize or test delivery time when enough data exists. Check the metric the system optimizes, eligibility requirements, and urgent campaigns that should not be spread across a long window.
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