Custom-domain email: forwarding, SMTP or a hosted mailbox?
Choose how to receive, send and reply with your domain. Compare forwarding, SMTP and hosted mailboxes, including storage, IMAP, costs and limits.
TL;DR
Forwarding delivers into an inbox you already have. SMTP submits outgoing messages. A hosted mailbox provides storage and access through its supported clients. Choose based on receiving, replies and storage together.
What you will learn
- Distinguish receiving aliases from outgoing identities and mailbox storage
- Choose a setup that works with your existing inbox or preferred client
- Check total costs, receiving limits and sending approval before changing MX
Choose the service that covers the whole conversation: where a message arrives, which address appears when you reply, and where the messages are stored.
Postscale fits application sending and qualified forwarding workflows. Its DNScale personal setup requires Starter or higher, forwards to the verified Postscale account inbox, and uses a separate sending approval process. It does not include a hosted IMAP mailbox or webmail. If you need a standalone inbox for each family member or employee, evaluate mailbox hosting first.
Compare the responsibilities
| Requirement | Forwarding only | Forwarding plus SMTP | Hosted mailbox |
|---|---|---|---|
| Receive at your domain | Routes to another inbox | Routes to another inbox | Delivers into hosted storage |
| Compose a new message as your domain | Needs another sending service | Yes, with an authorized identity and compatible client | Usually included; check plan and client support |
| Reply as your domain | Not established by forwarding | Configure and test the reply identity | Usually part of the account; aliases can have restrictions |
| Store incoming and sent mail | Destination inbox; forwarding is not mailbox storage | Destination inbox; client controls sent-copy location | Provider mailbox, subject to its storage policy |
| IMAP access | Comes from the destination mailbox, if offered | Comes from the destination mailbox, if offered | Check that the chosen host supports it |
| Many aliases or catch-all | Check address and traffic limits | Same, plus permitted sending identities | Check per-user, alias and storage allowances |
| Sending approval | No outbound capability established | Can require account or domain review | Provider policy still applies |
| Quota exhaustion | May defer, reject or charge overage | Check inbound and outbound rules separately | Check storage and sending behavior separately |
SMTP is a submission protocol, not an inbox. A forwarding address is a route, not a credential you can use to log in to an IMAP server.
Three setups that answer different needs
Keep an existing inbox and add a domain address
hello@your-domain.example → forwarding → existing inbox
Compatible client + domain identity → SMTP → correspondent
This can suit one person who likes their current inbox and is prepared to configure a client. Confirm that the client can associate the domain's From address with the intended SMTP service while retaining the original account's identity. Also check where replies and sent copies appear on your other devices.
Postscale's personal setup uses the verified account email as its forwarding destination. That inbox must be outside the domain being configured. Creating one address does not migrate every address previously served by the domain.
Choose a hosted mailbox for a complete account
Domain MX → mailbox host → webmail or supported IMAP client
Mailbox identity → host's sending service → correspondent
Choose this when you need mailbox storage, synchronized folders, multiple users, or one provider responsible for both the inbox and client access. Verify IMAP, export, aliases, recovery and migration support before choosing a host; the words “custom-domain email” do not establish those capabilities.
Keep business mail and add application sending
People writing to your team → existing mailbox provider
Application notifications → Postscale API / SMTP
You can keep receiving MX unchanged. Follow sending without changing MX instead of choosing personal forwarding or moving the company's incoming mail.
Add up the whole cost
Compare domain registration + DNS hosting + email service + destination mailbox + expected usage, including any client license. Some of those costs may already be paid, but a forwarding subscription does not replace mailbox storage you still need.
DNScale and Postscale have separate accounts, plans and billing. Postscale shares monthly email usage between sending and receiving. Check plan allowances and overage pricing and inbound limits against your expected traffic.
Ask any provider what happens to the next incoming message at a limit: acceptance, temporary deferral, permanent rejection and additional billing have different consequences. Do not infer unlimited traffic from “unlimited aliases.”
Check replies before moving receiving mail
Use a controlled address to test forwarding receipt, a new outbound message, a reply to forwarded mail, the correspondent's visible From and Reply-To, and sent mail synchronization. Repeat a send from your original inbox identity to make sure it still uses the expected service. Postscale's SMTP reference supplies the connection settings.
If you currently compose third-party-address mail in Gmail's web interface, read the Gmail Send as transition options before choosing a replacement workflow. Adding an SMTP service does not itself replace a webmail feature.
For multiple receiving addresses, compare named aliases, catch-all and mailboxes. If paid forwarding into an existing inbox fits your needs, review automatic DNS setup with DNScale. Prepare every receiving address before approving MX changes; old mailbox contents stay with the old host.
Set up personal forwarding →Frequently asked questions
- Does forwarding let me reply from my custom domain?
- Forwarding alone does not configure your sending identity. You need an authorized sending service and a client that can select the domain address, or a provider's supported reply-routing feature.
- Does Postscale provide an IMAP mailbox?
- No. Postscale personal setup forwards to the verified account inbox and supports SMTP sending subject to approval. It does not provide hosted IMAP, webmail or mailbox migration.