Seamless vs Warmup Inbox

SEvs

Two Outbound tools side by side: what each does, what it costs and who it suits.

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The verdict Side by side Plans and pricing Who each is for Other options

The verdict

On the data we hold, Seamless comes out ahead. Here is why, point by point.

What the data says

Only Seamless has a free plan to start on.
Warmup Inbox starts lower, at $15/mo against $147/mo.
Only Seamless has an MCP server, so an AI employee can work in it directly.
In our Outbound ranking, Seamless places 25 and Warmup Inbox 6 of 33.

Side by side

Seamless and Warmup Inbox compared
At a glance	SESeamless	Warmup Inbox
Starts at	$147/mo	$15/mo
Free plan	Yes	No
API	Yes	Yes
MCP server	Yes	No
Links	Visit	Visit

Plans and pricing

Seamless

Freeindividuals testing outreachFree
Basicsolo reps needing monthly credit refresh$147/mo

Warmup Inbox

BasicPer inbox per month; 75 warm-up messages a day. Volume discounts as you add inboxes.$15/mo
ProPer inbox per month; 250 warm-up messages a day plus custom templates and scheduling.$49/mo
MaxPer inbox per month; 1,000 warm-up messages a day plus API access and premium support.$79/mo

Prices as the vendors list them. They change often; the final price is on their sites.

Who each is for

Choose Seamless if…

We haven't written up who Seamless suits yet.

Visit Read the review

Choose Warmup Inbox if…

Sales, SDR and agency teams about to send cold email from new mailboxes, who need those mailboxes warmed up and monitored so campaigns reach the primary inbox.

Visit Read the review

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