Quick answer
Send from a platform with a properly authenticated sending domain, keep your list clean, avoid link shorteners and all-image emails, and send a test to yourself on two different mail providers before the real send.
Filters are judging the sender, not your wedding
Spam filtering is mostly reputation arithmetic: does this sending domain normally send mail people want? A personal email account sending ninety near-identical messages in four minutes looks, to a filter, exactly like a compromised account — which is one reason bulk invitations from a personal inbox land badly.
A platform that sends through an authenticated domain with proper email authentication records is starting from a much better position, and its reputation is maintained continuously rather than established in one burst.
What actually helps
- A verified sending domain with SPF, DKIM and DMARC configured correctly
- A clean list — bounced and invalid addresses removed rather than retried
- Real text in the email, not one large image with no words
- Direct links rather than URL shorteners, which filters treat with suspicion
- Honest subject lines with no manufactured urgency
What does not help
Removing the word "free", writing in title case, or avoiding exclamation marks are folklore from a decade ago. Modern filters weigh sender reputation and recipient behaviour far more heavily than any keyword in your subject line.
Bounces are information, not failures to retry
A hard bounce means the address does not exist — resending damages your reputation without reaching anyone. Suppressing that address permanently is the correct behaviour, and any decent platform does it for you automatically, including when the same address is added again for a different event.
A spam complaint is stronger still. Once someone marks a message as spam, they should never receive another non-essential message from the platform, regardless of who added them.
The pre-send checklist
- Preview the invitation exactly as a guest will receive it
- Send a test to a personal account on a different mail provider than your own
- Check the RSVP link opens on a phone, not just a laptop
- Confirm the sender name is one your guests will recognise
- Send to a handful of guests first if the list is large, then the rest
Tell guests to expect it
The single most effective thing you can do costs nothing: mention in the group chat or save-the-date that an invitation is coming, from which name, and to check the promotions or junk folder. A guest who is looking for your email will find it even if a filter files it awkwardly.
When to reach for a text instead
If a guest's email keeps bouncing or they simply do not use email, a text message with the same RSVP link solves the problem directly. That is a per-guest fix, not a reason to move the whole event to SMS.