---
title: Limits
description: Cloudflare Email Service has the following limits to ensure optimal performance and prevent abuse. These limits apply to emails sent via both the REST API and the Workers binding unless noted otherwise.
image: https://developers.cloudflare.com/dev-products-preview.png
---

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# Limits

Email sending quotas, rate limits, and how to request higher limits for production use

Cloudflare Email Service has the following limits to ensure optimal performance and prevent abuse. These limits apply to emails sent via both the [REST API](https://developers.cloudflare.com/email-service/api/send-emails/rest-api/) and the [Workers binding](https://developers.cloudflare.com/email-service/api/send-emails/workers-api/) unless noted otherwise.

## Daily sending limits

Your account may have daily sending limits based on Cloudflare's assessment of your account standing. These limits are applied on a per-account basis, may vary, and may be adjusted over time based on your sending behavior. If you need higher sending limits, contact [Cloudflare Support ↗](https://dash.cloudflare.com/support) to request an increase.

## Verified emails

When you first start using Email Service, you can send emails to [verified email addresses](https://developers.cloudflare.com/email-service/configuration/email-routing-addresses/#destination-addresses) in your account. This allows you to test and develop your application before sending to arbitrary recipients.

Accounts on a paid plan can send emails to any recipient, subject to daily sending limits.

## Email content limits

| Component                    | Limit          | Notes                                |
| ---------------------------- | -------------- | ------------------------------------ |
| **Recipients (to, cc, bcc)** | 50 per email   | Combined across all recipient fields |
| **Subject line**             | 998 characters | RFC 5322 compliant                   |
| **Total message size**       | 25 MiB         | Including attachments                |
| **Header size**              | 16 KB          | All custom headers combined          |

## Workers binding limits

The following limits apply only when sending emails via the [Workers binding](https://developers.cloudflare.com/email-service/api/send-emails/workers-api/). They do not apply to the REST API.

| Limit           | Value            | Notes                          |
| --------------- | ---------------- | ------------------------------ |
| **CPU time**    | 50ms per request | Standard Workers CPU limit     |
| **Subrequests** | 50 per request   | Includes email send operations |
| **Memory**      | 128MB            | Standard Workers memory limit  |

## Compliance

All email sending must follow applicable anti-spam laws and regulations to maintain good standing and deliverability.

* **CAN-SPAM Act** (United States)
* **GDPR** (European Union)
* **CASL** (Canada)
* Include proper unsubscribe mechanisms
* Honor opt-out requests promptly

Need a higher limit?

To request an adjustment to a limit, complete the [Limit Increase Request Form ↗](https://forms.gle/ukpeZVLWLnKeixDu7). If the limit can be increased, Cloudflare will contact you with next steps.

```json
{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/directory/","name":"Directory"}},{"@type":"ListItem","position":2,"item":{"@id":"/email-service/","name":"Email Service"}},{"@type":"ListItem","position":3,"item":{"@id":"/email-service/platform/","name":"Platform"}},{"@type":"ListItem","position":4,"item":{"@id":"/email-service/platform/limits/","name":"Limits"}}]}
```