Bulk Email Software: What 400,000 Emails a Month Really Costs
Cem Hurturk, Founder of Octeth
Updated First published
Most pages about bulk email software list a dozen tools with their cheapest plan. That price tells you nothing about what you will pay at volume. I have been building bulk email software since 1999, so this page does it differently: I priced 16 options at the same volume, 100,000 contacts and 400,000 emails a month, using each vendor's own pricing page on 2026-10-03.
The spread is wide: from about $40 a month in sending costs on a self-hosted platform to more than $800 a month on popular SaaS plans for the same 400,000 emails.
Short answer
| If you | Look at |
|---|---|
| Want everything managed and send under 100,000 contacts | A SaaS email platform: Brevo, MailerLite, Mailjet, Mailchimp |
| Send at high volume and want the lowest cost per email | A self-hosted platform plus a relay: Octeth, MailWizz, Sendy, Acelle Mail |
| Send for many clients or brands | Octeth, MailWizz (Extended), Acelle Mail (Extended) |
| Need your own IPs and several delivery servers | Octeth, MailWizz, Acelle Mail |
| Are a developer sending from your own app | A sending API: Amazon SES, SendGrid, Mailgun |
| Are thinking of a desktop sender app | Read the section on desktop senders first |
What is bulk email software?
Bulk email software sends one message, usually personalized, to a large list of subscribers at once. It manages the list, handles unsubscribes and bounces, and hands each message to a delivery server that sends it to Gmail, Outlook, Yahoo and other providers. Gmail itself caps personal accounts at 500 emails a day and Google Workspace users at 2,000, which is why bulk sending needs dedicated software.
The three types of bulk email software
- SaaS email platforms (Brevo, Mailchimp, MailerLite, Mailjet). Everything is managed: the software, the sending IPs and the deliverability. You pay monthly by contacts or by emails, and the price climbs steeply with volume. Our Mailchimp alternatives comparison prices 12 of them at 10,000 and 100,000 contacts.
- Self-hosted platforms (Octeth, MailWizz, Sendy, Acelle Mail). You run the software on your own server and send through a relay such as Amazon SES or through your own mail servers. The license is one-time or yearly. Sending costs are the relay's per-email price, often a tenth of SaaS pricing at volume. You own the operations.
- Desktop sender apps (SendBlaster, Atomic Mail Sender, GroupMail). Windows programs that send from your PC, either directly or through an SMTP server. They are cheap, but direct sending from a PC cannot meet today's provider rules, covered below.
16 options priced at 400,000 emails a month
100,000 contacts, 4 sends a month. Monthly billing unless noted. Prices from each vendor's site on 2026-10-03.
| Option | Type | Plan for this volume | Monthly cost | Sends through |
|---|---|---|---|---|
| Octeth | Self-hosted | Paid license from $5,500 one-time, plus relay | $40 to $64 Amazon SES, plus server | Any relay, PowerMTA, your own IPs, or Octeth-operated delivery |
| Amazon SES | Sending API | Pay per email | $40 (Ã la carte) or $64 (Essentials, the default for new accounts) | AWS shared IPs, dedicated IP $24.95 a month |
| Sendy | Self-hosted | $69 one-time, plus SES | $40 to $64 SES, plus hosting | Amazon SES, or SMTP per brand |
| MailWizz | Self-hosted | $79 lifetime or $59 a year, plus relay | Relay cost, plus server | Any SMTP or ESP, or your own servers |
| Acelle Mail | Self-hosted | $80 one-time, plus relay | Relay cost, plus server | SES, ESP APIs, SMTP |
| Mailtrap | SaaS | Pro, 100k contacts, 500k emails | $214 | Mailtrap IPs, dedicated IP included |
| Brevo | SaaS | Standard, 500,000 emails | $429 | Brevo shared IPs |
| MailerLite | SaaS | Comfort, 100k subscribers | $439 | MailerLite shared IPs |
| SendGrid Marketing Campaigns | SaaS | Advanced, 100k contacts | $450 | Twilio SendGrid IPs |
| Mailjet | SaaS | Premium, 500,000 emails | $499 | Mailjet IPs |
| Moosend | SaaS | Pro, 100k contacts | $624 ($499 billed yearly) | Moosend IPs |
| Mailchimp | SaaS | Standard, 100k contacts | $800 ($680 for the first 12 months) | Mailchimp shared IPs |
| ActiveCampaign | SaaS | No public price above 50k contacts | On request | ActiveCampaign IPs |
| SendBlaster | Desktop | Pro, €149 one-time | Your SMTP relay | Your SMTP server |
| Atomic Mail Sender | Desktop | $89.90 per PC | SMTP cost if external | Your PC, or an SMTP server |
| GroupMail | Desktop | $149.95 to $699.95 one-time | SMTP cost if external | Your PC, or an SMTP server |
A self-hosted platform also needs a server. Plan on about 4 vCPU and 8 GB of RAM for 100,000 subscribers, around $50 a month, and your time to run it. Our cost comparison shows how this adds up over a year against common SaaS plans.
The rules every bulk sender must meet
Since February 2024, Gmail and Yahoo have required bulk senders to authenticate and to make unsubscribing easy. Microsoft added the same rules for Outlook.com in 2025. These come from the providers' own pages:
| Rule | Gmail | Yahoo | Outlook.com |
|---|---|---|---|
| Who counts as a bulk sender | 5,000+ messages a day to Gmail accounts | Bulk senders (no number published) | 5,000+ messages from the same From domain |
| Authentication | SPF and DKIM, DMARC (p=none allowed), aligned From | SPF and DKIM, DMARC at least p=none, aligned | SPF and DKIM pass, DMARC at least p=none, aligned |
| Unsubscribe | One-click unsubscribe, honored within 48 hours | One-click (RFC 8058) plus a visible link, honored within 2 days | Not specified |
| Spam complaints | Keep under 0.10%, never reach 0.30% | Under 0.3% | Not specified |
| Enforcement | Rejections are increasing since November 2025 | Gradual since 2024 | Rejects with error 550 5.7.515 since 2025-05-05 |
Gmail and Yahoo also require valid forward and reverse DNS for the sending IP. That is the main reason sending straight from a home or office PC no longer works for bulk mail. Our free SPF record generator, DKIM generator and DMARC generator produce the records, and the SPF and DKIM checker verifies them.
Bulk email software with your own SMTP server
Every bulk email sends from an IP address, and that address carries a reputation. You have three options:
- Shared IPs (most SaaS plans). The vendor's reputation covers you, and other senders' behavior affects you.
- A dedicated IP at a relay or SaaS vendor, for example $24.95 a month on Amazon SES. Your reputation is yours alone, and the IP needs warm-up.
- Your own SMTP servers (Postfix or PowerMTA on servers you control). Full control and the lowest cost at very high volume, plus full responsibility for reverse DNS, warm-up, bounce and feedback-loop processing, and blocklist monitoring.
Desktop senders that send directly from your PC use the third option without the infrastructure behind it. Some even advertise proxy rotation and text spinning to get past spam filters. That is the opposite of what the provider rules above ask for, and it puts your domain at risk.
Self-hosted platforms let you mix these options. In Octeth, delivery servers are assigned per client group and per channel (marketing, transactional, autoresponder). One brand can send through Amazon SES while another uses your own warmed-up IPs. If you would rather not run mail servers, we operate delivery for customers on dedicated IPs with managed warm-up, bounce and feedback-loop processing, and blocklist monitoring. The IP warm-up planner shows what a ramp-up schedule looks like.
Where Octeth fits
Octeth is built for high-volume senders and agencies:
- Volume on your own infrastructure. Octeth's sizing guide lists about 100,000 emails an hour on 4 vCPU and 8 GB of RAM, and 500,000 an hour on 8 vCPU and 16 GB, assuming an optimal SMTP setup.
- Multiple delivery servers: Amazon SES, Mailgun, SendGrid, PowerMTA or any SMTP server, routed per client and per channel.
- Bounce, complaint and suppression handling, with Google Postmaster data inside the platform.
- Many brands or clients on one installation, each with its own limits and sender domains.
- Installation, onboarding and support from the team that builds it. A full setup takes two to four weeks.
If you send a monthly newsletter to a few thousand people, a SaaS free or entry plan is simpler. For a wider view of self-hosted tools, see our self-hosted email marketing comparison, and for the server side, our guide to choosing a VPS for email marketing.
Frequently asked questions
What is the best bulk email software?
For managed sending under 100,000 contacts, a SaaS platform such as Brevo or MailerLite. For high volume at the lowest cost per email, a self-hosted platform such as Octeth, MailWizz or Sendy with Amazon SES. For many clients, Octeth, MailWizz Extended or Acelle Mail Extended.
How do I send bulk email without landing in spam?
Authenticate with SPF, DKIM and DMARC, send only to people who opted in, add one-click unsubscribe, remove bounces and complainers immediately, keep complaints under 0.1%, and warm up new IPs gradually.
What are the Gmail, Yahoo and Outlook bulk sender requirements?
Senders of 5,000 or more messages a day to Gmail, or to Outlook.com from one domain, must pass SPF and DKIM, publish DMARC (p=none is enough) with alignment, and offer one-click unsubscribe (Gmail and Yahoo). Spam complaints must stay under 0.3%.
Can I send bulk email for free?
Small volumes, yes. Several SaaS platforms have free plans with daily or monthly caps, and open source tools such as listmonk are free to run. At 400,000 emails a month you pay either a SaaS plan (about $430 to $800 on the plans above) or relay costs ($40 to $64 on Amazon SES) plus a server.
How many emails can I send per day?
Gmail limits personal accounts to 500 a day and Google Workspace users to 2,000. Bulk software has no such cap. Your limit comes from your plan, your relay's quota and your IP reputation. New IPs must be warmed up.
Do I need my own SMTP server for bulk email?
No. SaaS platforms include sending, and self-hosted platforms can use a relay such as Amazon SES. Your own SMTP servers make sense at very high volume or when you need full control, and they bring reputation work with them.
Do I need a dedicated IP for bulk email?
Not below roughly 100,000 emails a month, where a good shared pool is usually better. Above that, a dedicated IP gives you your own reputation, and it needs consistent volume and warm-up.
Is sending bulk email legal?
Yes, with consent and compliance: CAN-SPAM in the US, GDPR and ePrivacy in Europe, and CASL in Canada. Send only to people who agreed to hear from you, identify yourself, and honor unsubscribes promptly.
What is the difference between bulk and transactional email?
Bulk email is one message to many people, such as newsletters and promotions. Transactional email is triggered by one person's action, such as receipts and password resets. Many platforms, Octeth included, route the two through separate delivery servers so a marketing campaign cannot hurt receipts.