You gave your email address to a shop once, three years ago. Since then it has been sold, copied into mailing lists you did not sign up to, and used by people you had no intention of hearing from. Nothing you did caused that. It is simply how ordinary email works: anyone who obtains your address can put something in front of you, and the best your provider offers is to guess afterwards whether you wanted it.
Opt-in email starts from the opposite end. This guide explains what it is, how it differs from a spam filter, and what actually happens to a message from someone you have not approved.
What opt-in email is
Opt-in email is a delivery rule: a message reaches your inbox only if you have already approved the sender. Approval is the default condition of delivery rather than something applied after the fact.
You build a list of people and organisations you want to hear from — family, your bank, the services you actually use. Mail from those senders arrives normally. Mail from anyone else does not reach the inbox at all. There is no folder to check, no digest to skim, and no judgement call to make about a sender you do not recognise.
How it differs from a spam filter
A spam filter guesses whether a message is unwanted after it has already arrived. Opt-in email decides whether the sender is allowed to arrive at all. That is the whole difference, and it explains why the two behave so differently over time.
A filter has to be right about every new message from every new sender, forever, against people actively working out how to word things so it is wrong. When it errs one way you get junk; when it errs the other way you lose something you needed. An approved-sender list does not have to make that judgement, because the question it answers is one you have already answered yourself.
What happens to mail from someone you have not approved
With OptMsg, a message from an unapproved sender goes to Trash rather than your Inbox, and is deleted automatically after 30 days. It is not silently discarded — you can look, and OptMsg’s Community Recommendations will flag a sender that many other people have chosen to trust, so a genuine message from an unfamiliar address is not lost.
Why this matters for phishing and identity theft
A phishing message can only work on you if it reaches you. Every convincing fake invoice, delivery notice and bank alert depends on arriving in a place where you are reading and half-trusting what you see.
This matters more as the fakes improve. Convincing scam messages are cheap to produce now, and advice like “look for spelling mistakes” has aged badly. Deciding in advance who is allowed to write to you does not depend on catching the tell.
If your Gmail or Outlook inbox is already overloaded
You do not have to abandon your existing address to try a different rule. Most people move gradually: keep the old account, forward it to a new OptMsg address, and approve senders as real mail comes through. Over a few weeks the list builds itself out of the correspondence you actually have.
The volume drop is usually the first thing people notice, and it is not because anything was filtered more aggressively. It is because most of what used to arrive was from senders you had not approved.
Plans
OptMsg offers different plans tailored to varying needs, from a basic Reader plan to more comprehensive Monthly and Annual Plan options with added features like community recommendations. Your OptMsg account also has no password, so a password stolen from another site cannot open your inbox.
You can read more about how the approved-sender model handles threats on our Security First page, or Create Your Account and start building your approved list.
FAQ
What is opt-in email?
Opt-in email is a delivery rule where a message reaches your inbox only if you have already approved the sender. Mail from anyone you have not approved does not arrive in the inbox at all.
How is opt-in email different from a spam filter?
A spam filter judges each message after it arrives and can be wrong in both directions. Opt-in email decides at the sender level, using a list you control, so no guess is needed.
What is permission-based inbox control?
Permission-based inbox control is another name for the same idea: delivery depends on permission you have granted in advance, rather than on a filter’s assessment of the content.
Will I miss an important email from someone new?
Mail from an unapproved sender goes to Trash rather than disappearing, and stays there for 30 days. Community Recommendations highlight senders trusted by many other OptMsg users, so a legitimate message from an unfamiliar address is easy to spot and approve.
