An alias is a second address that delivers into one of your mailboxes. Used sensibly, aliases give you a per-service identity that you can switch off without changing your main address. That makes them useful for privacy, and for finding out where a leaked address came from. This article covers how to use them well, and where they stop helping.
Aliases and plus-addressing
ITProMail supports two ways to create extra addresses. Plus-addressing gives you you+tag@itpromail.com, which arrives in your main mailbox and needs no setup. Aliases are separate addresses you create under Account > Aliases. Plus-addresses are convenient, but they are easy to recognise, and some services strip or reject them. A separate alias looks like any other address. Plus-addressing details are in subaddressing, and alias setup is in aliases.
One address per relationship
The core practice is to give each service its own address. A shop, a forum, a newsletter, a bank, and a job board each get a different alias. The benefit is that the address becomes evidence. If one alias starts receiving spam, or appears in a breach notice, you know which relationship exposed it, and you can disable that alias alone.
Without this, a single leak lets anyone holding the list correlate your accounts. With it, a leak has a boundary.
Breach tracing
When a service you use reports a breach, look at the address the notice was sent to. If it is the alias you gave that service, the breach is a likely source of later spam to that alias. If spam arrives at an alias you never gave to that service, that is a clue that the address list came from somewhere else, possibly a different breach or a broker. This is not proof, because data is shared and sold, but it is a useful signal.
Keep a simple record of which alias went to which service. A password manager's notes field works, as does a plain private spreadsheet.
Shutting an alias off
When an alias gets spam, remove it. You can do this without affecting your main address or your other aliases. Mail sent to a removed alias will be rejected or bounced, and some senders keep trying. The rejection tells them the address is dead, which is itself useful.
Plan this before you need it. If you change a service's contact address, update the account settings first, and remove the old alias only once you are sure the new one works.
Catch-all: useful, but read the trade-off
On the Shadow plan, a catch-all accepts mail to any address at a domain you own. It is powerful for disposable addresses, but it also accepts every misspelling, every guessed address, and every spam message sent to the domain. Use it deliberately and watch the volume. Many people keep catch-all off and create addresses one at a time.
What aliases do not do
Aliases are not a privacy tool against the mail provider. The provider can see mail sent to an alias, just as it sees mail sent to your main address. An alias does not hide your IP address, your browsing, or the content of messages. It limits correlation between services and makes leaks traceable. It is one layer among several, alongside the practices in tracking pixels and metadata is the leak.
Some services refuse plus-addresses, or aliases on particular domains, and some require a phone number for verification. Be prepared to use your main address in those cases, and do not reuse it elsewhere.
Plans and limits
The number of aliases depends on your plan. Recon includes two aliases, Operator includes ten, and Shadow includes unlimited aliases and a catch-all. Plus-addressing is not limited by plan. Custom domains, which give aliases a domain you control, require Operator or Shadow. See pricing for current details.