Frequently Asked Questions
Everything you need to know about email warming and Mailsim.
What is email warming?+
Email warming is the process of gradually building a positive sender reputation for a new or underused email address. By sending and receiving emails in a natural pattern over time, email providers learn to trust your domain and deliver your messages to the inbox instead of the spam folder.
Why do I need to warm up my email?+
New email accounts and domains have no sending history, so providers like Gmail and Outlook are more likely to flag your messages as spam. If you send cold outreach, newsletters, or transactional emails from an unwarmed account, your deliverability will suffer. Warming builds the trust signals that providers look for before placing your emails in the inbox.
How does Mailsim work?+
Once you connect your email account, Mailsim automatically sends emails from your address to our warming pool. Pool accounts then open, read, star, and reply to your messages — mimicking real human engagement. This generates positive signals that email providers use to evaluate your sender reputation. Volume starts low and gradually increases to avoid triggering spam filters.
How long does it take to see results?+
Most users see noticeable improvements in inbox placement within 2 to 3 weeks. Full reputation building typically takes 4 to 6 weeks depending on your domain age, sending volume, and starting reputation. Mailsim's dashboard lets you track your progress in real time.
Which email providers do you support?+
Mailsim supports Gmail, Google Workspace, Microsoft Outlook, Exchange Online, Yahoo, Zoho, and any provider that supports SMTP/IMAP. We also work with transactional email services like SendGrid, Mailgun, and AWS SES.
What is a Custom Template Test?+
Custom Template Tests let you send your actual email content — the exact template you plan to use in campaigns — to our test mailboxes. We then show you whether it landed in the inbox or spam, along with full email header analysis (SPF, DKIM, DMARC), spam confidence scores, and blacklist checks. It's like a dress rehearsal before your real send.
Will warming trigger spam filters or get my account flagged?+
No. Mailsim uses gradual ramp-up controls that start with very low daily volumes and increase slowly over time. This mimics natural email behavior, which is exactly what providers expect. The engagement from our pool (opens, replies, stars) further reinforces positive signals.
Can I cancel anytime?+
Yes. Mailsim offers both monthly and yearly billing options with no long-term contracts. You can cancel from the billing page at any time and your subscription will remain active until the end of your current billing period. Yearly plans include a 15% discount.
Is my email data secure?+
Absolutely. All email credentials are encrypted at rest using AES-256-GCM encryption. OAuth connections never expose your password. We do not read, store, or share the content of your personal or business emails — warming emails are generated by our system and are the only messages we interact with.
Do all plans include the same features?+
Yes. Every Mailsim plan includes automated warming, deliverability testing, blacklist monitoring, full header analysis, reputation tracking, and gradual ramp-up controls. There is no feature gating — the only difference between plans is the number of email accounts, daily volume limits and deliverability testing limits.
Do you offer a free trial?+
Mailsim starts building inbox placement and sender reputation as soon as you connect an inbox. While we don't offer a traditional free trial, your email warmup begins immediately and is designed for long-term email deliverability rather than short tests.
Can I change my plan later?+
Yes. You can upgrade at any time as your email warmup needs evolve.
When will I see results from email warmup?+
Most users see early improvements within the first few days/weeks, such as fewer emails landing in the spam folder. Stronger inbox placement and stable sender reputation typically build over 2 to 4 weeks of continuous email warmup. Complete warmup schedule is 10 weeks.
Is Mailsim safe for my domain?+
Yes. Mailsim is designed to warm up email accounts gradually and safely. The inbox warmup process reduces domain spam risks and protects your sender reputation by mimicking natural email behavior.
Do you support Gmail, Google Workspace, and Microsoft 365?+
Yes. Mailsim supports major email providers, including Google Workspace / Gmail and Microsoft 365 / Outlook, as well as other SMTP-based platforms.
Can you warm up multiple domains?+
Yes. You can warm up inboxes across multiple domains, which is ideal if you separate outreach by brand, team, or risk level to better control email deliverability.
What happens if I want to add more inboxes mid-month?+
You can add inboxes instantly and scale your email warmup service at any time. There's no need to wait for a billing cycle reset.
Do you offer onboarding or setup help?+
Yes. Our support team can help you connect inboxes, configure warmup Gmail accounts, and apply best practices to avoid spam filters and improve inbox placement quickly.
Do you offer refunds?+
If something isn't working as expected, contact our support team. We'll review your setup, identify issues affecting email deliverability, and help you fix them.
Is email warmup enough to fix deliverability issues?+
Email warmup is a critical foundation, but the best results come from combining it with proper DNS setup, list hygiene, and smart sending patterns. Mailsim helps you with the highest-impact actions to avoid the spam folder and improve long-term inbox placement.
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