How the price comparison works
Every price in the calculator is read from the provider's own pricing page or official pricing feed, stored with the exact text it came from, and re-checked every day.
Where prices come from
In order of preference: a provider's official machine-readable pricing (for example a published pricing API or pricing file), its official pricing page, its official documentation, and finally manual verification by our team. Third-party comparison sites are never used as a source. For every number we keep a short verbatim quote and the page it came from; a price only counts as verified while that quote can still be found on the provider's page.
Right now 22 of 115 products in our catalogue have verified pricing. The others stay listed as "not verified" or "custom pricing" — we never estimate a price to fill a gap.
When prices are checked
A crawler visits each official pricing page once a day, identifies itself as MailerflowPriceBot, follows robots.txt and never bypasses logins, captchas or blocks. If a page hasn't changed, the published prices are confirmed. If it has changed, the new data is compared with what we publish: small, fully evidenced changes can be accepted, everything else — price moves above 25%, disappearing plans, zero prices, currency switches, missing features or incomplete data — waits for a human review. Until then the previous verified price stays live. Each result shows the date it was last verified; prices not re-verified for 14 days are marked stale.
Some providers load their prices with JavaScript from internal services or refuse automated access. We don't scrape those internal services; such providers show "price unknown" for the list sizes we couldn't verify until we confirm them manually.
How the cheapest option is calculated
- For each provider we evaluate every plan and the add-ons it would need, and keep the cheapest combination that meets all hard requirements: your service type, contacts, monthly emails, required features, users, and known daily limits.
- A plan must fit both your contact count and your sending volume. Where a provider charges overage instead of upgrading, we compare both options.
- A feature counts only if the provider documents it for that plan (included or as a priced add-on). "Unknown" never passes a requirement, and a feature advertised somewhere on a site is not assumed to be in every plan.
- Free trials and promotional or first-period discounts are never used as recurring prices. Permanent free plans are used, with their contact, sending, daily and user limits.
- Results are sorted by monthly-equivalent cost; ties are marked and ordered alphabetically. Plans with documented limits that may not fit (daily caps, fair-use rules, warm-up limits for new accounts, undocumented allowances) are shown separately as conditionally eligible.
- Mailerflow runs this site and is listed like any other provider: its prices come from its live plan configuration and go through exactly the same rules. A short Mailerflow note appears below the results, never inside the ranking. There are no affiliate links; if that ever changes, it will be disclosed and will not affect rankings.
Billing, currencies and taxes
Monthly billing is the default. Annual prices are shown as a monthly equivalent and require paying a year up front. Prices are shown in the provider's currency when it publishes one; otherwise they are converted with the European Central Bank's reference rates (currently from Oct 9, 2026) and marked ≈ — you are billed in the provider's currency. VAT and sales taxes are excluded unless a provider says its prices include them.
What may not be included
SMS, WhatsApp and push credits, extra add-ons you didn't select, dedicated IPs unless required, onboarding or migration fees, attachment and data-transfer charges, and payment-processing fees. Self-hosted software is only compared together with the sending service and costs it needs; one-time licence fees are shown separately.
Report a wrong price or submit a correction
Are you a vendor, or did you spot an outdated price? Tell us what's wrong and, ideally, link the official page. We verify every report before changing anything.