These are Top best SMTP Extensions for Magento 2 Ecommerce:

1. Landofcoder Magento 2 SMTP Extension: Being the first place in this list, Magento 2 SMTP Extension on Landofcoder will bring to you the best experiences on powerful Features:Use Your Own SMTP Server Or Use A Popular Service, Take full control over Magento 2 SMTP settings, Run tests before sending out the mail, Block IP, Debug mode, ...

Link: https://landofcoder.com/magento-2-smtp-extension.html

2. Amasty Magento 2 SMTP Extension: This Magento 2.2 SMTP Extension allows to send reliable emails from a popular local hosting or a custom Magento 2 SMTP server. Take full control over Magento 2 SMTP settings and run tests before sending out the mail. Make sure that customers and partners receive all the emails you send.

Link: https://amasty.com/smtp-email-settings-for-magento-2.html

3. Megaplaza Free Magento 2 SMTP Extension: Magento 2 SMTP email settings will provide you a friendly configurable port and host, brief modules along with user guideline stick below the fields, that you can figure out its function easily.

4. Emizentech Free Magento 2 SMTP Extension:
Custom SMTP the most useful extension for the users coming up with highly accessible features. The Magento 2 smtp mail extension that can be used by the consumers for sending Magento emails directly through customized server settings. This magento 2 smtp module is eminently appropriate for the users who send emails using Magento server.

Link: https://store.emizentech.com/magento2/magento2-custom-smtp.html/

5. Neklo Magento 2 SMTP Extension:
Quick delivery of emails, Secure connection, Reliable email providers, No deliverability issues, Custom settings, ...

Link: https://store.neklo.com/custom-smtp-extension-for-magento2.html

6. Webkul Magento 2.2 SMTP Extension:
SMTP Configurator Magento 2 is a module by which store owner can easily set up an SMTP server on his web store so that all the emails send through his store will be sent by the selected host.
Magento 2 has included this Magento 2 smtp email settings so that tracking and sending emails through the store become easy.

Link: https://store.webkul.com/SMTP-Configurator-Magento2.html

7. ASchroder Magento 2.2 SMTP Extension

SMTP Pro is the best free, open-source SMTP solution for Magento. It gives merchants complete control of custom SMTP server settings for sending Magento emails and includes pre-configuration for popular services such as Gmail and Google apps.

Link: http://www.aschroder.com/product/smtppro-magento-smtp-email/

8. Ulmod Magento 2.2 SMTP Extension

Link: https://www.ulmod.com/blog/smtp-emails-for-magento-2-new-ulmod-extension/

9. Mlxstore Magento 2.2 SMTP Extension

Link: http://www.mlx-store.com/magento2-extensions/marketing/smtp-email-for-magento-2.html

10. Smart App SMTP Extension for Magento 2

Link: http://www.smartappsolution.net/magento-extension/magento-2-extensions/magento-2-custom-smtp.html

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