gsetz

This plugin prevents people from registering with disposable email addresses (dea) like the ones provided by mailinator (also known as throw-away email, one-time email). It protects your most important asset, your registered user base, by preventing contamination by fake accounts. This plugin working principle is similar to spam blacklists.
It hooks in the wordpress function is_email() so it will extend the known email validation of wordpress to detect dea domains.
The plugin itself does not contain a list of domains to block. Instead of local maintenance the plugin uses the service of http://www.block-disposable-email.com. This is a very accurate free service for up to 200 queries a month. For huge sites several commercial plans are available.
Please see the FAQ section for some more information.

Block Disposable Email

This plugin detects one-time email addresses (disposable email, trashmail, mailinator, 10minutemail) and helps to keep your userbase and comments clea …

Sajjad Hossain Sagor

Using This Plugin You Can Block Spammy Disposable & Temporary Email Domains From Submit On GravityForms form. Filtering Spammy Emails Will Keep Your Subscriber List Spam Free.
<h4>Features:</h4>
<ul>
<li>Designed As Plug & Play So That Anyone Can Use</li>
<li>Toggle Feature To Enable/Disable Blocking on Individual Form</li>
<li>Easily Change Disposable/Temporary Emails Found Error Message (Default Message Provided)</li>
</ul>
Are You Getting Too Much Spammy Disposable or Temporary Emails Submission On Your GravityForms form which are not much valuable? You can use this plugin to block/prevent disposable emails like 10MinuteMail and GuerrillaMail from submission on any GravityForms form.
Credits 
– https://github.com/andreis/disposable

Disposable Email Blocker – GravityForms

Prevent From Submitting Any Disposable/Temporary Emails On GravityForms Forms.

Block Disposable Email vs Disposable Email Blocker – GravityForms