Email-to-Case is the Salesforce Service Cloud feature that automatically converts inbound customer emails into Case records, threads every reply (and attachment) back to the same case, and routes it to the right agent or queue. You choose one of two modes: standard Email-to-Case, which uses a downloadable agent that runs behind your firewall, or On-Demand Email-to-Case, which runs entirely on Salesforce's Apex email services with no software to install. For most orgs, On-Demand is the recommended default.
Key takeaways
- Email-to-Case auto-creates a Case from every inbound email and links all replies to the original case via a thread ID.
- Standard Email-to-Case needs the downloadable Email-to-Case agent running behind your firewall, has no email size limit, and keeps mail on your own servers, which suits high volume.
- On-Demand Email-to-Case uses Salesforce Apex email services, needs no agent or software, sets up faster, but enforces an email size limit (~25 MB including attachments). It is the recommended default for most orgs.
- Both modes rely on routing addresses you create and verify, plus forwarding from your real support mailbox to the Salesforce-generated address.
- Pair Email-to-Case with assignment rules, auto-response rules, escalation rules, and Omni-Channel so cases land with the right agent and meet SLAs.
What is Email-to-Case in Salesforce?
When a customer emails one of your support addresses, Email-to-Case creates a new Case, auto-populates fields such as Subject, Description, Contact, and Email, and stores the original message (and any attachments) on the case. Salesforce embeds a unique thread ID in the email subject or body so that customer replies attach to the existing case instead of opening a duplicate. From there, assignment rules, queues, and Omni-Channel decide who works it.
This is the email equivalent of Web-to-Case, which captures cases from a form on your site. Many support teams run both channels into the same Case object.
Standard vs On-Demand Email-to-Case: which should you use?
Both modes produce the same end result, a Case, but differ in how the email is received and what limits apply.
| Factor | Standard Email-to-Case | On-Demand Email-to-Case |
|---|---|---|
| Software to install | Yes, the downloadable Email-to-Case agent behind your firewall | No agent or software; uses Salesforce Apex email services |
| Email/attachment size limit | No size limit (handled on your mail server) | Email size limit ~25 MB including attachments |
| Where email is stored | On your own mail servers until processed | Processed directly by Salesforce |
| Setup effort | Higher: install, configure, maintain the agent | Lower: enable and configure in Setup |
| Best for | High email volume; must keep mail on-premise; large attachments | Most orgs; fast setup with minimal infrastructure |
| Maintenance | You patch and monitor the agent | Salesforce-managed |
Bottom line: choose On-Demand unless you have a specific reason, such as very large attachments or a policy requiring email to stay on your own servers, to run the standard agent.
How do you enable and configure Email-to-Case?
The steps below apply to both modes; the only real difference is whether you install the agent (standard) or check the On-Demand option.
1. Enable the feature
Go to Setup and use the Quick Find box to open Email-to-Case (in older orgs the path is Setup > Customize > Cases > Email-to-Case). Click Edit, select Enable Email-to-Case, and to use the no-agent mode also select Enable On-Demand Service. Save.
2. Configure case settings
Still in the Email-to-Case settings, set how inbound mail is handled: the default case owner or queue, automated case user (this user receives an error notification whenever a message fails to create a case), thread-ID formatting, and whether to insert the thread ID in the subject, body, or both. Configure auto-response rules so customers get an instant acknowledgement with their case number.
3. Create and verify routing addresses
A routing address is the public support address your customers write to (for example support@yourcompany.com). For each one, click New, enter the routing name and email, choose the case priority/origin defaults, and save. Salesforce sends a verification email to that address; you must click the link to verify it before cases will flow.
4. Forward your support mailbox
Salesforce generates a long internal email address for each routing address. In your own email system (Google Workspace, Microsoft 365, etc.), set up forwarding from your real support mailbox to that Salesforce-generated address so inbound mail reaches the service.
5. Install the agent (standard mode only)
If you chose standard Email-to-Case, download the Email-to-Case agent from Setup and configure it to run against your mail server behind the firewall. On-Demand mode skips this step entirely.
6. Test
Send a test email to the routing address and confirm a Case is created with the right owner, and that a reply threads back to the same case.
What limits and rules should you plan for?
- On-Demand email size: the total inbound email, including attachments, must stay within the ~25 MB limit. Oversized mail is rejected, with an error sent to the automated case user. Standard Email-to-Case has no such cap.
- Routing address verification: a routing address only works after you click the verification link Salesforce emails to it. Re-verify if you change the address.
- Daily processing limits: On-Demand Email-to-Case runs on Apex email services, which are subject to org-wide daily inbound email limits scaled by your user licenses.
- No agent for On-Demand: there is nothing to patch or monitor, which removes a class of outages but means you accept the platform size limit.
For more complex inbound-email logic, such as parsing the body or creating custom records, you can write an Apex handler with Salesforce inbound email services.
How does Email-to-Case fit a modern support setup?
Email-to-Case is the channel; routing and SLA automation make it useful. Combine it with:
- Assignment rules to set the owner or queue based on subject, product, or region.
- Auto-response rules to send an immediate, branded acknowledgement with the case number.
- Escalation rules to reassign or notify managers when a case ages past its SLA. See how to set up Salesforce case escalation rules.
- Omni-Channel to push cases to available agents instead of static queues.
Salesforce has steadily made Email-to-Case the standard email channel for Service Cloud, with On-Demand as the default path because it needs no on-premise infrastructure. If your team needs help wiring this into a wider service process, our Salesforce consulting and development team can design routing, automation, and integrations end to end.
Frequently Asked Questions
What is the difference between Email-to-Case and On-Demand Email-to-Case?
Both turn inbound emails into Case records. Standard Email-to-Case uses a downloadable agent that runs behind your firewall with no email size limit, suiting high volume or large attachments. On-Demand Email-to-Case runs on Salesforce Apex email services with no software to install but enforces an email size limit. On-Demand is the recommended default for most orgs.
Do I need to install software for On-Demand Email-to-Case?
No. On-Demand Email-to-Case requires no agent or on-premise software. You enable it in Setup, create and verify routing addresses, and forward your support mailbox to the Salesforce-generated address. Only standard Email-to-Case needs the downloadable agent.
What is the email size limit for On-Demand Email-to-Case?
On-Demand Email-to-Case enforces an email size limit of roughly 25 MB, including attachments. Messages above the limit are rejected and an error is sent to the automated case user. Standard Email-to-Case has no size limit because mail is handled on your own server.
What is a routing address and why must I verify it?
A routing address is the support email your customers write to, mapped to a Salesforce-generated internal address. Salesforce sends a verification email to the routing address; you must click the link before cases will be created. This proves you control the mailbox and prevents misrouted email.
How does Salesforce keep email replies on the same case?
Salesforce inserts a unique thread ID into the email subject and/or body. When a customer replies, Email-to-Case reads that thread ID and attaches the reply, with any new attachments, to the original case instead of creating a duplicate.
Can I automate routing and escalation after a case is created?
Yes. Pair Email-to-Case with assignment rules to set owner or queue, auto-response rules for instant acknowledgements, escalation rules for SLA breaches, and Omni-Channel to push work to available agents. These run automatically once the case is created.