After Mailgun's December 2025 Flex plan price doubling ($1→$2/1K), self-hosted saves even more. At 50K/month: self-hosted $5/month vs Mailgun Foundation $35 (save $360/year). At 100K: $10 vs $90 (save $960/year). At 500K: $20 vs $275 (save $3,060/year). Self-hosted breaks even at ~17K emails/month. Below that, Mailgun's convenience wins. Above that, the savings compound fast.
Self-Hosted SMTP vs Mailgun: Real Cost Comparison at Every Volume
Cost Comparison (Updated March 2026 — Post Flex Price Increase)
At 10,000 emails/month
| Provider | Monthly Cost | Annual Cost |
|---|---|---|
| Mailgun Flex | $20 ($2/1K) | $240 |
| Mailgun Foundation | $35 | $420 |
| Self-hosted (Hetzner CX21) | $5 | $60 |
| Savings vs Mailgun Foundation | $30/mo | $360/yr |
At 50,000 emails/month
| Provider | Monthly Cost | Annual Cost |
|---|---|---|
| Mailgun Foundation | $35 | $420 |
| Mailgun Scale | $90 (overkill) | $1,080 |
| Self-hosted (Hetzner CX21) | $5 | $60 |
| Savings vs Foundation | $30/mo | $360/yr |
At 100,000 emails/month
| Provider | Monthly Cost | Annual Cost |
|---|---|---|
| Mailgun Scale | $90 | $1,080 |
| Self-hosted (Hetzner CX31) | $9 | $108 |
| Savings | $81/mo | $972/yr |
At 500,000 emails/month
| Provider | Monthly Cost | Annual Cost |
|---|---|---|
| Mailgun Scale+ | $275+ | $3,300+ |
| Self-hosted (Hetzner CX41) | $16 | $192 |
| Savings | $259+/mo | $3,108+/yr |
At 1,000,000 emails/month
| Provider | Monthly Cost | Annual Cost |
|---|---|---|
| Mailgun Custom | $450+ | $5,400+ |
| Self-hosted (Hetzner dedicated) | $40-50 | $480-600 |
| Savings | $400+/mo | $4,800+/yr |
The Real Comparison (Including Hidden Costs)
Self-Hosted True Cost
- VPS: $5-50/month
- Your time: 1-2 hours/month maintenance
- Monitoring: $0-10/month (HetrixTools free + n8n)
- Backup: $1-3/month
- Total: $6-63/month + time
Mailgun True Cost
- Plan: $35-275+/month
- Dedicated IP (optional): $59/month
- Your time: ~0.5 hours/month (dashboard checks)
- Total: $35-334/month
Break-Even Analysis
| Factor | Self-Hosted Wins When... |
|---|---|
| Volume | Above 17K emails/month (cost break-even) |
| Time value | Above 50K/month (savings exceed time cost) |
| Agency scale | 10+ clients (savings multiply per domain) |
| Control needs | You need full infrastructure ownership |
When to Stay on Mailgun
- Sending under 50K/month (savings don't justify effort)
- No technical resources for server management
- Need managed infrastructure with support
- Prefer convenience over cost optimization
- Just getting started and want simplicity
When to Switch to Self-Hosted
- Sending 100K+/month (saving $960+/year)
- Agency managing 10+ client domains (savings compound)
- Have technical comfort with Linux/Docker
- Want full control over sending infrastructure
- Ready to build monitoring automation (n8n)
Migration Path
- Start: Mailgun Foundation ($35/mo) — learn email infrastructure basics
- Grow: Mailgun Scale ($90/mo) — when volume demands it
- Optimize: Self-hosted Postal/Mailcow ($5-15/mo) — when savings justify setup
- Scale: Self-hosted + n8n monitoring ($15-25/mo) — full infrastructure stack
Don't jump to self-hosted on day one. Learn with a managed service first.
Practitioner note: The December 2025 Flex plan price doubling was the tipping point for several of my agency clients. At $2/1K, Mailgun Flex is no longer competitive for any meaningful volume. I migrated three agencies to self-hosted Postal in January 2026 — each saves $150-300/month. The setups took 4-6 hours each.
Practitioner note: The honest comparison: Mailgun is easier. Self-hosted is cheaper. If you value your time at $200+/hour and send under 100K/month, Mailgun might actually be more cost-effective. If you have a junior devops person or are comfortable with servers, self-hosted wins above 50K/month.
If you want to evaluate whether self-hosted makes sense for your volume, schedule a consultation — I'll do the math for your specific situation and handle the migration if it makes sense.
Sources
- Mailgun: Pricing
- Hetzner: Cloud Pricing
- Mailcow: Documentation
v1.0 · March 2026
Frequently Asked Questions
What changed with Mailgun pricing?
December 2025: Mailgun doubled the Flex (pay-as-you-go) rate from $1/1K to $2/1K emails. This makes their fixed plans (Foundation $35/mo, Scale $90/mo) essential. The price increase widened the gap between Mailgun and self-hosted.
At what volume does self-hosting make sense?
Financially: above ~17K emails/month (where Mailgun Foundation at $35/mo exceeds a $5 VPS). Practically: above 50K/month where the $30+/month savings justifies the setup effort. For agencies at 100K+/month across clients, the savings are compelling.
What about maintenance time cost?
Budget 1-2 hours/month for a Mailcow server. At $50/hour (consultant rate), that's $50-100/month in time. The break-even shifts higher: self-hosted saves money above ~100K emails/month when you factor in time. For agencies with technical staff, the time cost is negligible.
Should I use Mailcow or Postal for the self-hosted option?
Postal for GoHighLevel/application SMTP (delivery tracking dashboard, webhooks). Mailcow for full email server needs (send + receive + webmail). Both cost the same to run ($5-20/month VPS). See our comparison guide for details.
What are the risks of self-hosting vs Mailgun?
Self-hosted risks: server downtime is your problem, no support team, maintenance responsibility, IP could be dirty from previous tenant. Mailgun advantages: managed infrastructure, support, automatic scaling, no server management. The trade-off is cost vs convenience.
Want this handled for you?
Free 30-minute strategy call. Walk away with a plan either way.