What smtp server (provider) should I use to send bulk emails? (5000+)

Question

I am going to send emails to our users (5000+), but I'm not sure what's the best way to do it.

To send single emails we have used google apps' smtp server, which allows 100/day (or 400 if you pay). We're using PHP and PHPMailer.

1) How does i.e. google react if i send thousands of emails from my own smtp server? Do they use blacklists or whitelists?

2) Can I buy access to a 'trusted' smtp server somewhere? (I would actually prefer this solution)

3) What are the best practices when sending bulk emails? (send 50, wait 30 mins, send more ..etc ?)

Answer 1

As far as a 'trusted' smtp service goes, I can highly recommend: postmarkapp.com

Answer 2

What I have done in the past is done it batch at a time, like 500 a time. I dont have the code to hand as it was quite some time back but it was something like select 500 emails at each time using limit, send emails, sleep() for a bit and then get the next batch of 500, but i refreshed the page to get the next batch, like pagination and it ran really well. I did have just over 750000 users tho but it ran nice overnight. :-)

Increase your set_time_limit(); so your script dont time out and maybe your memory ini_set('memory_limit', 'xxM');

Not sure if you want to add a trigger in your db so that you are aware of who you sent it to incase it does fall over and you have to manually refresh, dont want to send it to them again.

I've used 1and1 and AUTHSMTP for SMTP servers. First choice would be 1and1 for me.

Answer 3

After some (extensive) searching and testing I found http://mailchimp.com to be best suited.

It has an api to maintain subscription lists, and forces you to obey spam rules :)

Answer 4

I'd recommend GoToCampaign http://gotocampaign.com

I liked their simple Rest based API that the have which you could try out with a free account and then upgrade to a Pay as you go plan ...

Answer 5

You should consider SocketLabs Email On-Demand for sending your newsletters - http://www.socketlabs.com/od.