Deliverability: landing in the inbox

Mail Merge sends through your own Gmail account. Whether a message lands in the inbox, in Promotions or in spam is decided by the recipient’s mailbox provider from your sending reputation, your domain’s authentication and the content, exactly as for an email you write by hand. A paid Mail Merge plan raises your daily limit; it does not change spam placement.

Check your domain first

Run the email reputation checker on your sending address. A missing SPF, DKIM or DMARC record is the most common reason bulk email is filtered, and it is fixed in your domain’s DNS, not in Mail Merge. Gmail and Yahoo require all three for anyone sending more than a few thousand emails a day, plus a one-click unsubscribe.

A free @gmail.com address is authenticated by Google already, but it has a low sending limit and no domain reputation of its own.

Warm up a new or quiet address

A new address, or one that suddenly sends 500 emails after months of silence, looks suspicious. Email warm-up builds engagement gradually with a network of real inboxes. Start it a week or two before a large campaign.

Send slower

Hundreds of identical emails in a minute is the signature of bulk mail. Turn on a delay between emails in Settings, or a random delay, and spread large lists over several days with Autopilot. See Email throttling.

Give people a way out

Add the unsubscribe link to every campaign. Recipients who can unsubscribe do not click “Report spam”, and spam complaints hurt your reputation more than anything else. Mail Merge also sends the one-click unsubscribe headers mailbox providers ask for.

Keep the list clean

• Remove addresses that bounced in a previous campaign (status Bounced or Error with a bounce note). Repeated sends to dead addresses are a strong spam signal.
• Do not send to purchased or scraped lists. Mail Merge has no built-in email verification; use a verification service before importing a list you did not collect yourself.
• Unsubscribers and blocked contacts are excluded automatically.

Content

• Personalize: a {{First name}} and a sentence that fits the recipient perform far better than a generic blast, and look less like bulk mail.
• Keep links to a few, on domains you own; avoid URL shorteners.
• Avoid all-caps subjects, spammy phrases and a single large image with no text.
• Send yourself a test and open it on a phone and in Gmail’s web interface.

Reading the signals

• “550 … spam rejected” or similar in an Error note: the recipient’s server refused the message. Fix authentication and content, slow down, and retry later.
• Cooldown rows: Gmail itself is throttling you. Reduce the daily volume; see Sending limits.
• Low open rate on a tracked campaign: likely spam placement. Check Analytics per campaign, and compare with a warmed-up address.