The best alternatives to Namekin are Nuage Email, Throttle, and AltMails. If these 3 options don't work for you, we've listed a few more alternatives below.
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By using AltMails email addresses, you will never have to give out your personal email ever again. Instead, you can use our email addresses for every service you sign up with, making it really hard for companies and advertisers to track you online.
at.market has more than 1000 domain names where you can get the email you've always wanted. Your second email address will use your current inbox so you can use it alongside the email address you already have.
IdBloc protects your privacy & security by generating permanent, anonymous email addresses on demand. Use IdBloc whenever someone wants your email address. Emails are automatically forwarded to your real address, keeping your identity secure.
Create proxy email addresses that forward to your real email address. Sign up for new services with a proxy email address. Use a new proxy email address for each service you sign up for in order to maximize your privacy. https://obscura.one