Best cold email warmup tool: a standalone warm-up service or the warm-up inside your outreach tool

Best cold email warmup tool: the short answer

If you already send cold email from Instantly, Smartlead or lemlist, the best cold email warmup tool is the warm-up inside that platform, because it comes with the plan. From any other sending tool, a standalone service fits: Warmy, MailReach or TrulyInbox. Prices are US dollars as read on October 23, 2026.

• Instantly or Smartlead when warm-up should come included with sending.
• MailReach for standalone warm-up billed per mailbox.
• Warmy to add placement tests and DMARC monitoring beside your sending tool.

Warm-up inside outreach plans: Instantly, Smartlead and lemlist

Instantly Growth is $47 a month billed monthly, with unlimited email accounts, unlimited warm-up and 5,000 emails a month. Instantly's warm-up page ramps from 2 emails on day one to 4 on day two and 6 on day three. Smartlead Base is $39 a month billed monthly, and its warm-up pool, the group of real mailboxes that exchange warm-up messages with yours, is at the Foundation tier; Pro moves up to the Growth tier.

lemlist's Email plan is $69 a month on monthly billing and $55 on yearly billing, and includes lemwarm, lemlist's own warm-up tool. Smartlead's page says the ideal warm-up for a new domain is 1 to 2 months, a vendor claim. Warmy vs Instantly and lemwarm alternatives compare warm-up on its own.

Standalone warm-up: Warmy, MailReach and TrulyInbox

Warmy's plans start from $49 a month, billed monthly, and its comparison pages list Starter at 100 warm-up emails a day. MailReach is $25 a month for 1 mailbox, billed monthly. TrulyInbox Starter is $29 a month billed monthly, and its page says warm-up runs at 2 warm-up emails for every 1 cold email.

Take a three-person agency that bought five secondary domains and 15 Google Workspace mailboxes for client cold email and must warm them up before launch. Per-mailbox tools bill each of the 15 mailboxes. Warmy prices by warm-up volume, and its pages disagree on how a plan counts mailboxes, so the agency asks Warmy first. Warmy's help center advises against using the primary domain for cold outreach.

Warmy's pages describe a 7-day free trial that lets one mailbox warm up beside your outreach tool before you pay for both. The Terms limit the trial to one mailbox and one user and convert it to a paid subscription unless you cancel before it ends.

What Warmy's terms say about cold email

Warmy's Terms of Service, revised October 1, 2026, say in sections 1 and 6 that Warmy does not authorize use of the service to send unsolicited commercial email, or to warm up sending for it, and bar uploading contact lists without all required consents. Read those sections against your outreach first. This page is not legal advice.

Warmy's help center also publishes cold-outreach warm-up guides: use a secondary domain, keep roughly a 2:1 ratio of warm-up to cold email, and start with 10 to 20 emails a day, though another of its articles says not to warm up below 100 a day. Its sending-process article says Warmy does not send cold outreach and is not a full deliverability solution for cold email.

Sending limits that matter more than warm-up

Google Workspace sets a daily sending limit of 2,000 per user account, and 500 for trial accounts, and says the limits can change without notice. Warmy's help center tells senders not to exceed their email provider's daily limits, so warm-up volume does not lift that ceiling.

Google's FAQ, read October 23, 2026, asks senders to keep their spam rate below 0.1% and never let it reach 0.3%. MailReach's blog says you may not need warm-up under 20 cold emails a day per inbox, a warm-up vendor's view. Best email warmup tools compares more options.