Terms of Use

The overarching agreement you make to work with MailerSend.

Last updated on April 12, 2024

The purpose of these Terms of Use (“Terms”, “Terms of Use”) is to introduce the basic terms and conditions of the services provided by MailerSend through its website and mobile application.   

MailerSend is a product created under the corporation whose legal name is MailerSend, Inc. (228 Park Ave S, PMB 54955, New York, New York 10003-1502, US) “MailerSend”. MailerSend provides transactional email (and additionally for U.S. based customers—transactional and/or marketing SMS (SMS)) services ("Services").  

Please note that throughout these Terms, "we," "us," and "our" refer to MailerSend, and "you," "your," and "yours" refer to the user.

1. General rules

1.1. MailerSend undertakes to provide the Services in the best business manner and in accordance with the Terms of Use and all laws applicable to MailerSend.  

1.2. To use our Service you must: 

  • Be at least eighteen years old; 

1.3. By signing up or using the site, you accept these Terms and warrant that you meet all the requirements listed in this document as well as you will not use the Services in a way that violates these Terms or any laws or regulations. If you violate any of it, we may suspend or terminate your account.  

2. Payment terms

2.1. Payment is not made until the provision of Service. The payment period is one month for a monthly plan and can be settled by a credit card. In the event that you exceed your Services limit, you must pay for the exceeding part additionally.  

2.2. The rates for Services and additional services provided by us are listed at Prices do not include VAT or other taxes of any kind. We may modify or change our fees and pricing at any time. 

3. Delivery and Filtering 

3.1. MailerSend will use commercially reasonable efforts to deliver your email and / or SMS messages, but MailerSend does not guarantee delivery. Third-party filtering services and other policies of recipient email / SMS services may prevent the successful delivery of your email and / or SMS messages.  

3.2. While the MailerSend Services do provide some email filtering services designed to filter spam it does not provide virus scanning and MailerSend recommends that you employ additional security measures to protect against spam, email phishing attempts, and emails infected with viruses. You acknowledge that the limitations of the filtering service will likely result in the capture of some legitimate emails and the failure to capture some unwanted emails, including emails infected with viruses.  

3.3. MailerSend is not responsible for any damages arising from the failure of the MailerSend Services’ filtering services to filter unwanted emails or SMS or from the capture of legitimate emails, or from a failure of your email or SMS to reach its intended recipient.  

4. Communications

4.1. Communications means transmissions sent via API (i.e. via email or SMS). You acknowledge and agree that MailerSend may occasionally send you communications regarding your account or the Services via email.

5. Accounts, passwords and security

5.1. You must be a registered user to access Services. You are responsible for keeping your password secure. You will be solely responsible and liable for any activity that occurs under your username. 

5.2. If your account is inactive for 6 months or more, MailerSend reserves the right to permanently delete your account with all its data, including your list of recipients, your sending and account activity, and your content. In the event of automatic deletion due to account inactivity, you will receive email notifications 30 days, 7 days, and 1 day prior to the permanent deletion of your data, with no option for data recovery.

5.3. MailerSend utilizes the service Have I Been Pwned, with their terms of use here, to proactively monitor and safeguard your email and password against potential data breaches. Should your account information be detected in any publicly disclosed datasets, we will promptly notify you and provide actionable steps to secure your account. This process involves only encrypted data checks, meaning that no third party can see or access your details and no personal data of yours is transferred to any third party. By agreeing to these terms, you grant your explicit consent to these security measures. 

6. Appropriate communication practices

6.1. Using MailerSend you can send two types of emails—transactional emails and marketing emails. Transactional emails are automated emails that you send to facilitate transactions or provide a product or a service. Marketing emails are newsletters that you send with the sole purpose of marketing your product or service.  

6.2. Using MailerSend you can send two types of SMS—transactional SMS and marketing SMS. Transactional SMS are automated SMS that you send to facilitate transactions or provide a product or a service. Marketing SMS are SMS that you send with the sole purpose of marketing your product or service. In doing so, you must comply with all applicable laws and rules, including but not limited to Cellular Telecommunications Industry Association (CTIA) Messaging Principles and Best Practices (please read about this here), which means: 

6.2.1. the latest version of the CTIA Messaging Principles and Best Practices, as amended, supplemented and/or superseded from time to time by the CTIA; or 

6.2.2. any other similar documents or guidelines promulgated from time to time by the CTIA. 

6.3. In order to send transactional emails and / or SMS using Services, you should ensure and be able to provide proof that emails and / or SMS are sent to the recipients based on:  

  • Permission-based subscriptions (“opt-in”); 

  • Contracts concluded between you and your customer; 

  • The purposes of legitimate interests; or 

  • Other legal grounds.

6.4. It is absolutely not acceptable nor allowable to send transactional emails and / or SMS to the recipients whose data was purchased, rented, or acquired from a third-party. 

6.5. To send marketing emails or SMS using Services, you must have consent from the recipient to receive these emails or SMS according to applicable laws and regulations (e. g. General Data Protection Regulations (Regulation (EU) 2016/679 of the European Parliament and of the Council of 27 April 2016 on the protection of natural persons with regard to the processing of personal data); or according to section 7, paragraph 2, number 3 UWG (Act Against Unfair Competition)—(opt in)—or have a business relationship with the advertiser, and the conditions according to article 13 section 2 of the European Parliament and Council Directive 2002/58/EC on Privacy and Electronic Communication are met, and etc.). 

6.6. Every marketing email you send using MailerSend must include a single-click, clear and visible unsubscribe link added using MailerSend's "track unsubscribes" feature that instantly adds the recipient to your MailerSend suppression list. Once they unsubscribe, you must stop sending them marketing emails. 

6.7. Every transactional or marketing SMS you send using MailerSend must include clear instructions on how to opt-out by including the sentence: “Reply STOP to unsubscribe” at the end of the initial message sent to the consumer, or “reply STOP to cancel”. Once they opt-out, you must stop sending them SMS. 

6.8. MailerSend reserves the right to terminate any account that it finds in violation of its Terms of Use by receiving abuse complaints higher than allowed, without refund.

7. Appropriate content

7.1. We allow sending only relevant content, which is agreed to receive by recipients and corresponds to the CAN-SPAM Act. Ineligible use cases:

High-Risk Financial Services

Get Rich Quick Schemes

Illegal Substances/




Any type of loans

Debt consolidation


Ethical hacking services

Quick credit

Debt reduction


Fraud or scams


Credit repair programs

Tobacco or vape

Deceptive marketing


Affiliate marketing

Mobile unlocking services

Profanity or hate speech

Stock alerts

Pyramid schemes


Content that encourages discrimination



Content that in any case could cause health-risk


Escort services

Weight loss material

7.2. You can send transactional and marketing emails and / or SMS using MailerSend only if the content is created by you or you have the right to use it. You represent and warrant that you either own or have permission to use all of the material, content, data, and information, including your personal information and the personal information of others, you submit to MailerSend in the course of using the Service. 

7.3. MailerSend may review the content from your account to ensure compliance with these terms. 

8. Confidential information

8.1. Each party agrees not to use the other’s confidential information (confidential information means non-public information disclosed by one party to the other in any form that (i) is designated as “Confidential"; (ii) a reasonable person knows or reasonably should understand to be confidential; or (iii) includes either party’s products, customers, marketing and promotions, know-how; and which is not independently developed by the other party without reference to the other’s Confidential Information or otherwise known to the other party on a non-confidential basis prior to disclosure, “Confidential Information”) except in connection with the performance or use of the Services, the exercise of its legal rights under this Terms, or as required by law, and will use reasonable care to protect Confidential Information from unauthorized disclosure. Each party agrees not to disclose the other’s Confidential Information to any third party except: (i) to its representatives, provided that such representatives agree to confidentiality measures that are at least as stringent as those stated in these Terms of Use; (ii) as required by law; or (iii) in response to a subpoena or court order or other compulsory legal processes, provided that the party subject to such process shall give the other written notice of at least seven days prior to disclosing Confidential Information unless the law forbids such notice. 

9. Routing data

9.1. Your email messages and other items sent or received via the mail service will include information that is created by the systems and networks that are used to create and transmit the message including information such as server hostnames, IP addresses, timestamps, mail queue file identifiers, and spam filtering information (“message routing data"). You agree that MailerSend may view and use the email message routing data for our general business purposes, including maintaining and improving security, improving our services, and developing products. In addition, you agree that MailerSend may disclose email message routing data to third parties in aggregate statistical form, provided that MailerSend does not include any information that could be used to identify you. 

10. Multiple account abuse

10.1. Creating multiple accounts is forbidden. Therefore you, as a natural person, must not: 

10.1.1. create multiple users and / or; 

10.1.2. create different accounts with the same domain or different subdomains and / or; 

10.1.3. login with different login credentials.  

10.2. The Customer, as a natural person, shall create only one account, where all the Customer’s domains shall be maintained.   

10.3. MailerSend may, at its sole discretion, allow the creation of multiple accounts. 

11. Limitation of Liability

11.1. In no event shall MailerSend be liable or responsible in any way in relation to the contents and use of, or differently in connection with this website or mobile app, or for any indirect, special, incidental or consequential damages (including but not limited to loss of use, loss of profits, revenue, income or anticipated savings, business losses, loss of reputation or goodwill, loss of contracts or business relationships, or loss and/or corruption of information or data) whether in an action in contract, equity or otherwise, arising out of or in any way connected with the use of or inability to use this site or mobile app or the materials therein or resulting from unauthorized access to or alteration of data. We will not be held liable for any delays or failure in performance of any part of the Service if it is prevented or delayed in performing those obligations by an event of force majeure circumstances. 

12. Suspension of Services 

12.1. MailerSend may suspend the Services without liability if: (i) MailerSend reasonably believes that the Services are being used in violation of the Terms; (ii) you do not cooperate with our reasonable investigation of any suspected violation of the Terms; (iii) there is an attack on the Services or your Services are accessed or manipulated by a third party without your consent, (iv) MailerSend is required by law or by a regulatory or government body to suspend the Services, or (v) there is another event for which MailerSend reasonably believes that the suspension of the Services is necessary to protect the MailerSend network or our other customers. Services might be reinstated after a suspension for non-payment or your breach of the Terms only when the payment is received or the breach is remedied.  

13. Termination of Service

13.1. The term of Service will continue for as long as you have a MailerSend account or until you or we terminate it. 

13.2. We reserve the right to terminate your account at any time with or without cause. You also have the option of canceling your account at any time without penalty. In the event of account cancellation, you will lose all data related to your account. 

14. Refunds

14.1. We are required to provide a refund only if we terminate our Services to you without cause before the end of a billing period. There is no other circumstance in which you will be entitled to a refund from us, including:

14.1.1. We do not provide refunds if your account is suspended because of violation of these Terms or our API Use Policy.  

14.1.2. We do not refund any unused or partially used plans (monthly or yearly) when you did not use or partially used the Services, and/or forgot to cancel your plan, and/or if you canceled immediately after your credit card was charged for the new billing period. A refund will not be applied if you purchased a wrong monthly/yearly plan (even by mistake), and/or decided to cancel your subscription after the purchase because of functionality.

14.1.3. We treat all customers equally, so we don’t make exceptions to these Terms.

14.2. We may, at our sole discretion, offer refunds in exceptional situations subject to any user seeking such refund applying for the refund in accordance with the requirements we post on the website or in the mobile app, which may be changed from time to time. In any case, the refund can only be made within 30 days from the last transaction date. 

15. Account Disputes

15.1. In the event of internal disputes involving MailerSend accounts, you shall resolve the matter directly with the other party. You shall not request access to or information about an account that you do not have access to. 

15.2. MailerSend reserves the right to suspend any account associated with the dispute to protect the security and privacy of the data held within the account until the dispute is properly resolved. Please note that we will request a copy of the court decision or other legitimate document in order to suspend the account. 

16. Conditions

16.1. We may modify or terminate our Services at any time, for any reason, and without notice. We reserve the right to modify these Terms of Use at any time without notice. Please review these Terms of Use on occasion as they may change in the future. We may, but have no obligation to, remove accounts and content containing what we determine as unlawful, offensive, threatening, defamatory, obscene or otherwise objectionable material. We will remove content that violates any party’s intellectual property or these Terms of Use. 

17. Disclaimer

17.1. MailerSend makes no commitment to provide any services other than the Services stated in the Terms. MailerSend is not responsible to you or any third party for unauthorized access to your customer data or for unauthorized use of the Services that is not solely caused by MailerSend’s failure to meet its security obligations as set in Privacy Policy

18. Intellectual property

18.1. MailerSend claims no intellectual property rights over the material you provide to the Service.  

18.2. You acknowledge that MailerSend owns all right, title, and interest in and to the Service, including without limitation all intellectual property rights, and such rights are protected by international intellectual property laws. You agree that you will not copy, reproduce, alter, modify, or create derivative works from the Service. 

19. Privacy

19.1. At MailerSend, protecting your privacy and the privacy of anyone receiving your communications is very important. Therefore, please read our Privacy Policy to know more about how we process and protect personal data in accordance with good industry practice. 

20. Changes

20.1. MailerSend reserves the right to change these Terms of Use at any time. If we decide to change this document, we will post changes on this page. All changes are effective immediately upon posting and we suggest that you check these Terms of Use periodically. 

21. Miscellaneous provision

21.1 These Terms of Use will begin upon the moment from which you become our client and will continue unless terminated hereunder.