The honest answer: there is no universal best day — only a best day for your audience. Industry studies put Tuesday, Wednesday and Thursday at the top, but a B2C retailer and a B2B SaaS will not behave the same way. The best day is the one your numbers prove.
Patterns most senders see
| Day | Strengths | Watch out |
|---|---|---|
| Monday | Catches week planners early | Inboxes are crowded with weekend backlog |
| Tuesday | Highest opens for many B2B lists | Competition is also at its peak |
| Wednesday | Mid-week sweet spot | Similar to Tuesday |
| Thursday | Good clicks before weekend planning | Friday and weekend mood starts |
| Friday | Lower volume, less competition | Many B2B readers disengage |
| Saturday/Sunday | Strong for B2C, lifestyle, travel | Weak for B2B and corporate |
How to find your best day
Pick two candidate days, send the same campaign to two equal halves of the same segment, and compare opens, clicks and conversions. Repeat across 3–4 sends to be sure the result isn’t a fluke. Pair it with the right hour using best time to send a newsletter.
Don’t forget frequency
The best day means little if you send too rarely or too often. See how often to send newsletters for the cadence side of the equation.
Industry research
Two recent reads: best day of the week to send emails and which are the best days to send.
Test, don’t guess
Run a 2-day A/B test across two consecutive sends and let the open/click rates pick the winning day. Mailpro’s reports show everything you need.