This is a follow-up to the popular Hints on better mass email sending article.
If a large part of your email messages are not delivered, chances are they are being deleted by antispam filters by mistake.
Here is a list of guidelines you should always follow when creating your email messages.
- If you’re using HTML emails, include a text part in the email as well, for recipients (and anti-spam checkers), and keep that text as close to the HTML copy as possible. The closer they’re related, the less likely your email will be seen as spam.
- Keep your message’s layout as simple as possible. Avoid complex formatting (yes, it will make it look better, but less people will receive it).
- Pay particular attention to your mailing’s subject: never use exclamation point (!), CAPITALIZATION, and words as “free”, “guaranteed”, and gappy text (t h i s i s g a p p y t e x t)
- Avoid generic salutation formulas as “Dear User”; it is even better to avoid salutation at all.
- If you’re using HTML emails, use high quality HTML emails. Don’t use tools which generate horrendous HTML (example: MS Word). They often leave signs behind (like empty tags, eg: ) which are generally found in spam. Unbalanced tags and invalid tags will also flag an email as spam. If you use a title, make sure the title is meaningful — the default titles generated by HTML tools are often used as spamsign.
- Don’t insert too much graphic in your message. The less images you use the better you’ll message will get through.
- Avoid attaching files; use links to files hosted on a web server instead.
- Use email composition and mailing tools that work correctly. Well constructed emails (technically correct) can be readily identified as not-spam. Emails with missing MIME sections, invalid or missing message-ids, invalid or missing date headers, subject or other headers with unescaped unicode, etc., are frequently signs of spam.
- Avoid useless or needless encodings. Don’t use base-64 encoded text unless you need to.
- Don’t include a disclaimer that your email isn’t spam. Don’t claim compliance with some legal criteria, especially one which is not actually law in your country. Only spam needs to claim compliance: non-spam is supposed to already be in compliance.
- Use normal conversational language, be sure not to use excessive spacing and or capitalization on your subject.
- Do not use “cute” spellings, Don’t S.P.A.C.E out your words, don’t put str@nge |etters 0r characters into your emails.
- If you’re using HTML emails, do not use invisible web-bugs to track your emails. If you must track your emails and whether they’re read, use visible graphics as part of your email, not invisible graphics.
- Don’t include gratuitous references to spam subjects. Don’t talk about rolex watches, sexually oriented activities or drugs, or debt treatment, unless those topics directly relate to your email. And if they do, limit your email to one topic at a time. An email which mentions rolex watches, Viagra, porn, and debt all in one email will very possibly hit several rules that flag it as spam, even if everything else is clear.
- Don’t use tools used by spammers (i.e., advertised in spam).
- Use a well performing, well administered and trusted SMTP server. Most undeliverable mails come from poor SMTP services, which often lead to being blacklisted: make sure your SMTP service’s staff is ready to help if you are blacklisted by mistake.
- Be careful where you advertise, and be careful which advertisements you carry. If you advertise with companies that send out spam, your domains will be flagged as being related to spam. If you carry advertisements for those who spam, your domains will be flagged as being related to spam.
- Be careful which domains/companies you allow to advertise in your emails (if any). Allowing spammers to advertise will get your emails flagged by the URI blacklists. On the other hand, don’t advertise your domains with spammers — having your domain name listed in their spams can also get you flagged by some URI blacklists.