How to send high volume cold email [beyond Gmail’s limits]

If you’re a cold emailer using any cold email platform other than mine, you’re likely subject to limits in the hundreds of emails per day. For most people, that allowance of a few hundred emails/day is enough, since it’s quite hard to find more than even 100 targeted prospects’ email addresses per day, where your message is relevant enough to the prospect that it doesn’t seem spammy.

But, let’s say you’re just that good at finding leads and capturing email addresses. Let’s go crazy here for a second and say you’ve fine-tuned a process that brings in 5,000 new email leads per day, and every day, you want to email these 5,000 email addresses and set a follow-up sequence that sends every few days until they reply. Now you’re in deep, because not only do 5,000 new email messages need to send every day, but once the follow-up schedules start to kick in, you’ll actually be sending more than 5,000 emails/day, when you take into account the original message volume and the follow-up email volume.

So, given G Suite’s limits of 2,000 emails/day and most cold email platforms’ own limits, how can you accomplish this?

You could set up multiple G Suite accounts and eventually send 2,000 emails per day per account. However, as years of experience has shown, it doesn’t always work so smoothly, and often times G Suite caps an account’s sending volume at a level much lower than 2,000 emails/day. This can work for some users but won’t work for most.

Last year, I invented a way to integrate an SMTP service or multiple SMTP servers into a high volume cold email process such that you can send as many emails as you want through an SMTP server like SendGrid, while preserving the ability to detect replies and send follow-up emails to non-responders. We do this through a little bit of inventiveness in how we relay the emails through an SMTP and sync the data back to your G Suite account.

Recent High Volume Cold Email Campaigns

Here is a sampling of recent large cold email campaigns sent by our platform in the last few weeks. Included are the number of auto follow-up stages and the open and reply rates. Some of these were distributed in daily batches via Gmail and some were sent via a third party SMTP relay.

This cold email campaign data is updated daily.

From Address	Subject	Follow-up Stages	Recipients	Open Rate	Replies	Date
mackenzie@xxxxxxxxxxxxx.com	F__l 2__6 S_______e E___: 5 P______s W___h Y__r A_______n	1	2,505	98.7%	5	08/28/26
glnyevents@xxxxxxxxxx.com	Y____e I______: An E_______e E_____g at G___a L___v S__o	1	3,162	83.3%	114	08/27/26
okan@xxxxxxxxx.com	L____n d____s | O_____r 8	1	2,478	78.0%	39	08/27/26
ahmed@xxxxxxxxx.ca	T___S B______S -___K TO S____L	1	4,967	65.8%	19	08/27/26
hello@xxxxxxxxxxxxxxxxx.uk	⭐️ T__s w_____d 🎨 70 s____s 🎶 L__e m_______s 🌮 K__B 🪩 A________y	1	6,388	61.0%	0	08/26/26
siddharth@xxxxxxxxxxxx.com	W___e g_______g N___h A_______s f____t e_______s t______r i_______g y_u	1	3,620	60.9%	12	08/24/26
sofiia@xxxxxxxxxxxx.com	L__t w__k f_r A____t B_____s ! C____n C__b i_______.	2	2,189	55.9%	25	08/24/26
nora@xxxxxxxxxxx.com	{____t N___} | {______t l___}	1	5,027	55.7%	20	08/26/26
siddharth@xxxxxxxxxxxx.com	W___e g_______g E______s f____t e_______s t______r i_______g y_u	1	3,449	54.4%	2	08/24/26
MatthewStar@xxxxxxxxxxxxxxxxxxxxx.com	W___e a_______g a 1______t p______y at 52 c___s on t_e d____r	2	2,241	51.9%	21	08/29/26
innovations@xxxxxxxx.in	R__U W______s 4G – AI S____y T__t S____s Up B____e R__k B_____s an I______t	2	5,079	51.1%	47	08/25/26
brian@xxxxxxxxxxxxxxxxxxxxxx.com	{___________________________________________________g F__________________________________________g O_____d s____} I______e C______, {_____________e E______e E____?	1	4,104	51.0%	9	08/27/26
katierose@xxxxxxxxxxxxx.com	N_w F__l B____y L_______: W___y L_x A___e C___r D___t & P_____n S___e L___e L_p B___s	1	3,309	50.8%	16	08/24/26
tanishq.sharma@xxxxxxxxxxx.in	A t_______s o_________y to w__k w__h t_e w_____s #1 c________r f_______e b___d	1	2,081	50.7%	265	08/24/26
brian@xxxxxxxxxxxxxxxxxxxxxx.com	Y__r {________} o_____g	1	2,016	45.5%	5	08/24/26
sarah@xxxxxxxxxxxxxxxxxxxxxxxxxxxx.uk	S______g R__k M________t C____________, E________t f_r {___________________}	0	12,119	43.8%	1	08/25/26
lindsey@xxxxxxxxxxxxx.com	N_W L_____: O____N T____d O_e of I_s B__t P_________e F_____s I__o a B_______p	2	2,616	42.5%	23	08/24/26
producerscout@xxxxxxxxxxxxx.com	We a_e l_____g f_r p_______s at B___________s	1	3,642	40.3%	34	08/26/26
arina@xxxxxxxxxxxxxx.com	�_3 F__E T________P S_____S F_R Y_U | W__________C	1	2,045	39.3%	31	08/24/26
nora@xxxxxxxxxxx.com	{____t N___} | {______t L___}	1	4,992	39.2%	11	08/25/26

Steps to sending high volume cold email:

1. Set up your G Suite account, and connect it to GMass.
2. Set up a SendGrid account or any other SMTP service and subscribe based on the daily volume of emails you want to send. When determining daily volume, take into account the original message plus follow-up emails that need to go out per day.
3. Connect SendGrid, or your alternate SMTP service to GMass.
4. When you launch your cold email campaign in GMass, set the SMTP option instead of Gmail.
5. Configure your auto follow-ups.
6. Hit the GMass button to launch the campaign.

What happens next?

Even though your emails are being sent by SendGrid, you’ll still see a copy of each individual email in the Sent folder of Gmail. When someone replies, the reply will still be threaded to the same conversation as the email in the Sent folder. And if someone doesn’t reply, and a follow-up email sends automatically in a few days, that follow-up will also be threaded to the same email conversation.

But wait, I’m not technical enough to set up SendGrid!

If setting up your own SMTP service is too complicated, and you don’t want to bother with the implications of DNS records, SPF, DKIM, DMARC, and all the subtleties that are recommended for deliverability, you have a couple of options:

1. Sometimes we allow users to use our SMTP service — but typically for cold email that isn’t opt-in, we don’t.
2. There’s a fiverr gig these days where someone will help you configure a SendGrid account for use with GMass.
3. You sign up for SendGrid and subscribe, and then send us your credentials and we’ll link GMass to SendGrid for you.

By the way, if you’re an advanced web developer and this all sounds to easy for you, you may want to read my technical review of SendGrid to take a look under the hood and see if you want to customize your SMTP process. That review is written specifically for advanced web developers. 

How high is our volume?

When you’re shopping different cold email platforms, ask them how much email they send. Then check our real-time counter for how much email we’ve sent. We’ve sent over 1 billion emails through Gmail and G Suite accounts. Not all of them were cold email campaigns, but a lot of them were.