How important is grammar and spelling?

You've probably received an email where a subscriber's name was replaced by a raw merge tag like "{first_name}" or a subject line had a typo in the company's own name. It's hard to unsee. These small errors create a quick impression: the sender either didn't check, or something broke. Neither is reassuring when you're asking someone to click a link or trust you with their inbox.

Grammar and spelling matter for two distinct reasons. The first is credibility. Consistent errors signal carelessness, and in email that perception costs you clicks and, over time, unsubscribes. The second is more technical: certain spam filters recognize patterns common in phishing and bulk unsolicited mail, including deliberate misspellings ("Fr3e g!ft") and unconventional capitalization designed to slip past keyword matching. A single typo in a legitimate email won't usually move your spam score noticeably, but repeated unusual patterns can contribute.

The error category that actually hurts deliverability is broken merge tags. Sending "Hi {first_name}," to tens of thousands of subscribers is both a content failure and a technical signal: it tells mailbox providers your sending infrastructure isn't reliable. Most ESPs let you set fallback values for personalization fields so that if the first name field is empty, the email reads "Hi there," instead of a broken token. Use them. Then run a seed send before any large deployment to catch these issues before they go out at scale.

A practical proofreading process doesn't have to be elaborate. Write the email, step away, then re-read it cold. If your team has the bandwidth, a second set of eyes catches things the writer's brain autocorrects over. For campaigns going to a large segment, a test send to a dedicated seed account lets you view the rendered email in-client and catch both formatting problems and broken personalization in one pass. Review My Emails's test send tool makes this step fast enough that it becomes routine. For a broader look at what can go wrong before sending, see the pre-send testing checklist.