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How We Warm Up Your Reputation

If you’re new to Gro and your first big campaign is going out slower than you expected, this page explains why. Short version: it’s deliberate, nothing is lost, and it’s the single best thing we can do for your open rates.

Gmail, Outlook, Yahoo and every other mailbox provider keep a reputation score for the servers and domains that send them email. A sender with no history that suddenly sends tens of thousands of emails looks exactly like a spammer, and gets treated like one: emails land in the junk folder, or get throttled, or bounce.

The fix is the same one every serious email platform uses. Start small, grow the volume steadily, and let the providers see that people open your emails and don’t complain. After a few weeks they trust you, and from then on you can send at full speed.

We call this warmup. It runs automatically for every new account. You don’t need to set anything up.

When you send a campaign during warmup, every email is queued as normal. Each day, Gro sends up to that day’s allowance. Anything over the allowance stays in the queue and goes out in the next day’s window. Emails are never dropped and you never need to resend.

Within a day, we also spread the allowance out rather than sending it all in one burst, because bursts are another spam signal.

On the campaign page you’ll see a Warming up badge next to Sending, along with how many emails are still queued and the date we expect the last one to leave.

Warmup day 1 is the day of your first campaign send. Days reset at midnight UTC.

Warmup daysDaily campaign allowance
1 to 3500
4 to 72,000
8 to 145,000
15 to 2115,000
22 to 2840,000
After day 28No cap

Automations (abandoned cart, welcome flows and so on) are not held back by the allowance. They’re triggered one at a time and are time sensitive, so they always go straight out. They do count toward the day’s total.

You can follow your own progress at any time under Settings > Email warmup.

Warmup completes on its own once the 28 days have run with healthy results. From that point your campaigns are no longer rate limited and you’ll see a Warm status on the warmup page.

Two things can pause the ramp:

  • Bounce rate too high. Too many addresses that don’t exist or reject mail. This usually means an old or imported list that hasn’t been cleaned.
  • Spam complaint rate too high. Recipients are marking your email as junk. This usually means people didn’t expect to hear from you, or can’t remember signing up.

If either happens, the ramp holds at the current step. Your sends carry on at that day’s allowance, they just don’t grow until our team has looked at what’s going on. We’ll be in touch if we need anything from you.

If you’re switching to Gro from Klaviyo, Mailchimp or another platform, you still go through warmup, but it’s usually smoother. Your domain already has a history, which the providers take into account. What they haven’t seen before is your domain sending from our servers, and that combination is what needs to be established.

A few things make a real difference:

  • Verify your own sending domain under Settings > Domains before your first campaign. Sending from your own domain, rather than a shared one, means the reputation you build is yours.
  • Import only engaged contacts. Bringing across everyone who ever signed up, including people who haven’t opened anything in two years, is the fastest way to trip the bounce and complaint limits.
  • Start with your best segment. Send your first campaigns to recent buyers and regular openers. Their opens and clicks are what teach the providers to trust you.

If you have a large, proven list and a long clean sending history elsewhere, get in touch. We can shorten the ramp for accounts that clearly don’t need the full schedule.

  • Keep sending. A gap of several days mid-warmup slows things down. Steady beats bursty.
  • Make unsubscribing easy and honour it immediately. Gro adds one-click unsubscribe headers to every campaign automatically.
  • Watch your first few campaigns’ bounce and complaint numbers on the campaign page. If bounces are high, clean your list before the next send.
  • Don’t buy or scrape lists. Ever. It’s the one thing that will get an account held every time.

If a campaign seems stuck, check Settings > Email warmup first. It shows today’s allowance, how much has gone out, and the expected finish date. If something still looks wrong, reach out to support and mention warmup so we can look at the timeline for your account straight away.