---
title: "Mail Reader Sampler"
description: "Configure the JMeter Mail Reader Sampler samplers: properties, defaults, and practical usage notes for building reliable load tests."
url: https://docs.jmeter.ai/components/mail-reader-sampler/
lastUpdated: 2026-10-01
source: docs.jmeter.ai
---

# Mail Reader Sampler

*Part of the **Samplers** category. Also documented in context in the [full Component Reference](/user-manual/component-reference/#mail-reader-sampler).*

![Mail Reader Sampler](/images/screenshots/mailreader_sampler.png)

The Mail Reader Sampler can read (and optionally delete) mail messages using POP3(S) or IMAP(S) protocols.

| Name | Required | Description |
| --- | --- | --- |
| Name | No | Descriptive name for this element that is shown in the tree. |
| Server Type | Yes | The protocol used by the provider: e.g. `pop3`, `pop3s`, `imap`, `imaps`. or another string representing the server protocol. For example `file` for use with the read-only mail file provider. The actual provider names for POP3 and IMAP are `pop3` and `imap` |
| Server | Yes | Hostname or IP address of the server. See below for use with `file` protocol. |
| Port | No | Port to be used to connect to the server (optional) |
| Username | No | User login name |
| Password | No | User login password (N.B. this is stored unencrypted in the test plan) |
| Folder | Yes, if using IMAP(S) | The IMAP(S) folder to use. See below for use with `file` protocol. |
| Number of messages to retrieve | Yes | Set this to retrieve all or some messages |
| Fetch headers only | Yes | If selected, only the message headers will be retrieved. |
| Delete messages from the server | Yes | If set, messages will be deleted after retrieval |
| Store the message using MIME | Yes | Whether to store the message as MIME. If so, then the entire raw message is stored in the Response Data; the headers are not stored as they are available in the data. If not, the message headers are stored as Response Headers. A few headers are stored (`Date`, `To`, `From`, `Subject`) in the body. |
| Use no security features | No | Indicates that the connection to the server does not use any security protocol. |
| Use SSL | No | Indicates that the connection to the server must use the SSL protocol. |
| Use StartTLS | No | Indicates that the connection to the server should attempt to start the TLS protocol. |
| Enforce StartTLS | No | If the server does not start the TLS protocol the connection will be terminated. |
| Trust All Certificates | No | When selected it will accept all certificates independent of the CA. |
| Use local truststore | No | When selected it will only accept certificates that are locally trusted. |
| Local truststore | No | Path to file containing the trusted certificates. Relative paths are resolved against the current directory. Failing that, against the directory containing the test script (JMX file). |

> **Note**
> You can pass mail related environment properties by adding to `user.properties` any of the properties described [here](https://javaee.github.io/javamail/docs/api/com/sun/mail/pop3/package-summary.html).

Messages are stored as subsamples of the main sampler.
Multipart message parts are stored as subsamples of the message.

**Special handling for “`file`” protocol:**

The `file` JavaMail provider can be used to read raw messages from files.
The `server` field is used to specify the path to the parent of the `folder`.
Individual message files should be stored with the name `n.msg`,
where `n` is the message number.
Alternatively, the `server` field can be the name of a file which contains a single message.
The current implementation is quite basic, and is mainly intended for debugging purposes.

## Related

- [API Load Testing Guide](/topics/api-load-testing/)
- [cURL & HAR to JMX Converter](/tools/curl-to-jmx/)
- [Full Component Reference](/user-manual/component-reference/)
- [Functions and Variables](/user-manual/functions/)