Mailwarmup vs SendScale Email Warmup

Mailwarmup is a web service that aims to raise sender reputation by generating positive email engagement through a shared network of more than 10,000 inboxes. After users connect an account using SMTP and IMAP details, it sends scheduled messages on their behalf. Network inboxes open and reply to messages, mark them important, and remove them from spam. A dashboard tracks warmup results, including messages removed from spam, categories, and email deliverability. Listed integrations include Gmail, Outlook, and SMTP; users can control sending and limits. Other listed tools include a Mail Health Score, blacklist monitoring, delivery statistics, blacklist removal prompts, and AI ramp ups in beta. Warmup messages can be filtered into a separate folder using the subject keyword “WUA.” There is no free plan, but a 7-day trial is offered. Starter costs $19 a month for one email account and up to 50 positive engagements per day. Growth is $49 a month for three accounts and up to 50 engagements daily; Scale is $99 a month for eight accounts and up to 100 daily; Powerhouse is $149 a month for eight accounts and up to 300 daily. Warmup does not guarantee inbox placement.

SendScale Email Warmup is a service for warming email accounts and building sender reputation for cold outreach. It connects Google Workspace and Microsoft 365 inboxes through OAuth, then uses AI to exchange unique messages between accounts in a private network SendScale says contains more than one million inboxes. The service says its system opens and scrolls through messages and replies in human-style language. If a warmup email lands in spam, SendScale says it moves the message out, marks it important, and replies. A dashboard tracks daily sends and replies, spam-versus-inbox placement trends, and readiness. SendScale recommends 14 days for new domains and says the dashboard indicates when warmup is complete; warmup can continue at lower volume while campaigns run. The service also describes account rotation for load balancing and a Master Smartbox for consolidating replies. Its free plan includes pre-warmed inboxes, warmup tools, in-product conversational guidance, and campaign access. Paid plans start at $28/mo billed annually. The privacy policy places database servers exclusively in the European Union and describes industry-standard security measures.