Definition
Paid inbox alternatives range from spam filters (classify after arrival) and email aliases (hide an address) to cover-charge gates like sift.mx (unknowns pay before delivery; trusted contacts stay free).
What problem are you solving?
Most people mix three goals: reduce noise, hide a real address, and stay reachable for the right strangers. Filters, aliases, and covers each optimize a different slice. Using the wrong tool for the job is why “I already have spam filtering” often still feels like drowning.
Spam filters
Provider filters and blocklists reduce noise inside an address that is already public. They help with bulk junk and known bad actors. They do not stop strangers from taking a free shot at you, and aggressive settings bury real mail.
Best fit: cleanup on an address you must keep public for legal or operational reasons—and as a second layer behind a gated handle.
Aliases and forwarding
Aliases hide your real mailbox and make it easier to burn a leaked address. Alone, they usually still accept unlimited free mail from unknowns. You traded identity leak risk for the same free firehose under a different name.
Best fit: per-site signups, throwaway merchants, and reducing how often your root address appears in databases—not as a complete cold-email strategy.
Pay-to-deliver covers
sift.mx combines private forwarding with whitelist rules and a member-set cover. Unknowns prove intent with payment; people you trust skip the fee. You keep the inbox you already use; senders never see it.
Best fit: founders, creators, and public-facing roles who need a publishable contact address without making attention free. Combine with normal filters on the destination inbox if you want.
Quick comparison
Filters: cheap, familiar, reactive. Aliases: good privacy hygiene, weak against free spam. Covers: change sender incentives, require a product people will pay into, and need a whitelist so friends are not charged.
Other paid-inbox products may host mail or charge differently. sift.mx’s distinct bets are private forwarding into your existing inbox, covers paid to you, and the same handle for E2E member chat.
A simple decision rule
If the pain is “my real address leaked,” start with aliases or private forwarding. If the pain is “strangers still interrupt me for free,” you need a price on access—not another folder. If the pain is both, use a gated handle (privacy + cover) and keep filters on the destination.
FAQ
Is sift a full email host?
No. It is private forwarding plus rules and covers in front of an inbox you verify elsewhere.
Can I use filters and a cover together?
Yes. sift.mx is the outer gate; your provider filters can still run on the destination inbox.
How is this different from a simple alias?
Aliases mostly hide an address. A cover also prices unknown delivery so spray outreach is not free.