Knowledge Base Deliverability Deliverability & warmup

Deliverability & warmup

Deliverability is whether your email actually lands in the inbox instead of spam. The biggest lever for a new sending domain is warming — ramping your daily volume up gradually so mailbox providers learn to trust you. This guide explains how RadarSend warms a domain and how to keep your reputation healthy.

What warming is and why it matters#

A brand-new sending domain has no reputation, so mailbox providers (Gmail, Outlook, Yahoo, and the rest) treat a sudden burst of email from it as suspicious — and route it to spam or reject it outright. Warming avoids that by capping how many emails the domain sends per day and raising that cap in steps as a clean track record builds.

In RadarSend a new domain starts around 200 emails/day and reaches full speed (50,000/day) over about eight weeks. You compose and schedule broadcasts as normal — RadarSend just paces how much actually goes out each day. A broadcast larger than today’s cap automatically spreads over several days, sending a little more each day as the cap grows.

Choose a warming plan#

Warming lives on each sending domain’s Details page. Go to Settings → Sending → Sending domains → your domain → Details and find the Warming plan card. There’s a How warming works explainer link on that card if you want the full walkthrough.

Warming is set per domain × sending service: each sending service (provider) connected to a domain gets its own independent track, so if you send the same domain through two providers, each warms separately. On the Details page, the header strip shows a Service tracks count, and each track appears as its own row with its own controls.

For each track you pick one of three presets — the difference is how long the domain holds at each step before moving up:

  • Conservative — holds each tier for 10 days. Best for a brand-new domain with no prior sending reputation anywhere.
  • Standard (Recommended) — holds each tier for 7 days. The typical path for a newly configured domain on a new sending service.
  • Fast — holds each tier for 3 days. Only for a domain that has prior sending history elsewhere (for example, migrating from another platform). Picking Fast without prior reputation risks bounces.

Every plan climbs the same eight tiers, from 200/day up to 50,000/day: 200 → 500 → 1,000 → 2,500 → 5,000 → 10,000 → 25,000 → 50,000. Each track shows its state as Off / Not warming, On (with its current tier, e.g. Tier 3 of 8), or Paused. Use Start warming to begin, Pause to hold (paused days don’t count, so you resume exactly where you left off), and Exit warming to finish.

How a track moves up: each night RadarSend checks every warming track and advances it one tier when it has spent enough time at the tier (the preset’s per-tier days) and has actually sent enough volume at that tier. The domain only warms if you actually send — a track left idle simply holds where it is until it sends again. If your list is small, warming stops climbing once the current cap already covers your largest recent audience: the track shows Warmed / At ceiling and holds there rather than ramping toward volume you’ll never send.

Track your reputation#

The domain Details page is your reputation dashboard. At the top, a metric strip shows First seen, Identities linked, Service tracks, and Google Reputation (Connected / Not connected).

Two areas track deliverability health:

  • Reputation signals — rolling 14-day averages captured daily, charted over the last 30 days: Hard bounce (notification threshold 1.0%), Complaint (0.05%), Click rate (no threshold), and Unsubscribe rate (0.5%). If bounces or complaints run hot, you get a notification and a Watch flag — but that’s a heads-up only; it doesn’t freeze your warming ramp.
  • Google Reputation (Google Postmaster Tools) — daily reputation signals for Gmail and Google Workspace recipients, including a domain-reputation rating (high / medium / low / bad) with 14-day history.

Connect Google Postmaster Tools: in the Google Reputation card (or the Connect Google Reputation step in the setup checklist), click Connect Google Postmaster and authorize your Google account. Your sending domains must first be registered at postmaster.google.com; RadarSend then pulls daily reputation data. The connection is read-only — RadarSend never acts on this data automatically, and you can Disconnect at any time.

Deliverability best practices#

  • Send only to people who opted in. Permission is the foundation of deliverability — never buy or scrape lists. High complaint rates from unwanted mail sink your reputation fast.
  • Keep your list clean. Remove addresses that hard-bounce or never engage. Poor list hygiene drives up bounces, which mailbox providers penalize.
  • Authenticate your domain. Set up SPF, DKIM, and DMARC so inboxes know your mail is legitimate — see Authenticate your sending domain.
  • Honor unsubscribes and subscription preferences. Make opting out easy and instant — see Email types & subscriptions.
  • Watch your bounces. Keep an eye on the hard-bounce signal and let suppression do its job — see Bounces & suppression.

Common issues#

  • “No reputation data yet.” Signals populate only after your first sends through the domain. Send a broadcast and check back the next day.
  • “My warming track isn’t moving up.” Advancement needs both time and volume at the current tier — a track that isn’t sending enough holds its tier. If your list already fits the current cap, the track is Warmed / At ceiling and won’t climb further (that’s healthy).
  • Google Reputation data is stale. If the last poll failed or is more than a few days old, you’ll see a stale banner — click Reconnect to refresh your Google credentials.
  • “No domains found” after connecting Google. Your Google account connected, but your domains aren’t registered in Postmaster Tools. Add them at postmaster.google.com, then click Connect again.
  • I want to send full volume immediately. You can skip or exit warming, but sending at full volume on a cold domain can hit receiver reputation thresholds quickly. It’s not recommended without prior reputation.

Good to know#

  • Warming is per domain × sending service. The same domain sent through two providers warms independently on two tracks.
  • You still schedule normally. Warming only paces delivery; broadcasts larger than today’s cap spread across days automatically.
  • Reputation signals are advisory, not gates. A Watch flag warns you when bounces or complaints are elevated, but warming keeps advancing on time and volume — you decide how to respond.
  • Pausing is free. Paused days don’t count against your progress; resume right where you left off.
  • Warming finishes on its own. Once a domain has genuinely earned the top tier, the cap comes off and it sends at full speed from then on. You can also exit early at any time.
  • Use a subdomain for marketing (e.g. news.acme.com) so bulk-sending reputation stays separate from your primary domain’s transactional mail.