A read across the ten most relevant email service providers shows a single, uniform onboarding posture: nearly every major platform includes custom domain authentication as part of standard onboarding and uses a shared, pre-warmed default to get senders live in minutes. The monetization gate sits one layer deeper — at the dedicated IP, where prices range from $21 to $59 per month and serve as the field's clearest infrastructure monetization layer.
If you remember nothing else from this brief, remember these. Each one is independently verified across all ten platforms surveyed.
Read together, these four numbers tell the story of the modern ESP market: onboarding is free, sending is rationed, and the dedicated IP remains the clearest infrastructure monetization point.
The single visualization a C-level reader needs. Bars show monthly add-on price for a dedicated sending IP, the field's clearest infrastructure monetization layer. Dashed markers indicate platforms where dedicated IP exists but is not self-serve.
Filter by category to see how each cohort handles the same five decisions: default domain, free volume, custom domain pricing, dedicated IP, and the primary upsell lever.
| Provider | Default domain | Free / entry volume | Custom domain | Dedicated IP | Primary upsell lever |
|---|---|---|---|---|---|
Mailchimp Marketing-first |
● Pre-warmed Shared mc.com infra |
500/mo · 250/dayFree tier · paid scales 10–12× contacts |
● Free DNS records only |
Enterprise onlyNo published price |
Automation gated behind $20+/mo Standard. Contact-count billing — unsubscribes still count. Actual bills run 20–40% over list. |
Brevo Marketing-first |
● Pre-warmed Falls to @brevosend.com |
~9K/mo · 300/dayFree; paid removes daily cap |
● Free Required or fallback domain used |
$21/mo · Pro+ only $251/yr · free on Enterprise |
Volume-based, not contact-based — distinctive in field. Dedicated IP gated at Pro. Logo removal +$12/mo on Starter. |
Constant Contact Marketing-first |
● Pre-warmed Shared CC infra |
60-day trial onlyLite from $12/mo · 500 contacts |
● Free DNS records only |
Not offeredNo clear IP path |
No permanent free tier — forces paid from day 61. Limited deliverability tooling. No upmarket infrastructure ladder. |
Klaviyo Ecommerce-first |
● Pre-warmed Shared Klaviyo / SendGrid infra |
500/mo · 250 contactsFree; paid unlimited sends |
● Free DNS records only |
Enterprise onlyNot standard self-serve |
Profile-based billing since Feb 2025 — all contacts billed, engaged or not. Soft overages auto-upgrade plan. No annual discount. |
Omnisend Ecommerce-first |
● Pre-warmed Shared Omnisend infra |
500/mo · 250 contactsPaid from $16/mo · 6K sends |
● Free DNS records only |
Not offeredNot publicly available |
Shopify / Woo-native — ecommerce-only audience. SMS bundled. Contact + volume gates run in parallel. |
HubSpot CRM-first |
● Pre-warmed Shared HubSpot infra |
2,000/moFree, branded · Starter $20/mo |
● Free DNS records only |
BundledAfter $3–7K onboarding fee |
No workflows on Starter — forces $890+/mo Professional. Mandatory onboarding ($3–7K) — largest in industry. |
ActiveCampaign CRM-first |
● Pre-warmed Shared AC infra |
14-day trialStarter $19/mo · 1K contacts |
● Free DNS records only |
AvailableNot prominently priced |
Full automation on ALL paid tiers — explicit anti-HubSpot position. No onboarding fees · free migration. Dedicated IP not pushed at SMB. |
SendGrid Infrastructure (Twilio) |
● Pre-warmed Shared IP pools on Essentials |
100/day · 60-day trialEssentials $19.95/mo · 50K/mo |
● Free CNAME domain auth |
$30/mo · included on Pro ($89.95+) +$30 each additional IP |
Dedicated IP is the primary upsell — gated at Pro. Essentials: no IP, no sub-users. Free plan removed in 2025. |
Mailgun Infrastructure (Sinch) |
● Pre-warmed Shared pools on Basic/free |
100/day · ~3K/mo freeFoundation $35/mo · 50K |
● Free 1 domain free · 1K on Foundation+ |
$59/mo · included on Scale ($90/mo) Highest in field |
Pure infra play — no marketing tools. Pay-as-you-go doubled to $2/1K in Dec 2025. Overages $1.10–$1.80/1K. |
Amazon SES Infrastructure (AWS) |
○ None Verification required day one |
Sandbox until approved$0.10/1K after — cheapest in field |
● Free Required from day one |
Self-managedNo IP upsell · Elastic IPs via console |
Pure infrastructure — no marketing layer. Sandbox approval required before live sending. Reputation, bounces, suppression all DIY. |
Nearly every major ESP, regardless of category, moves customers along the same path. The accent step is the primary infrastructure monetization layer — the gate where the most defensible recurring revenue is captured.
Pre-warmed shared domain. Immediate sending. Daily or monthly cap enforced.
DKIM / SPF setup. Effectively universal across the ESP field. A retention tool, not a revenue lever.
Monthly cap removal, automation, segmentation, A/B, branding removal. First real dollars.
The primary infrastructure upsell across the field. Reputation isolation. Warmup required.
Dedicated AM, SLA, custom onboarding. HubSpot's $3–7K mandatory onboarding sits here.
The market is also evolving beyond the older assumption that every serious sender eventually requires a dedicated IP. Several modern ESPs increasingly rely on highly segmented shared infrastructure with sophisticated reputation management — particularly for mid-volume senders. In many cases, intelligently managed shared pools now outperform underutilized dedicated IPs that haven't been properly warmed.
The strategic distinction is shifting from simply "shared vs. dedicated" toward how effectively platforms segment reputation, throttle traffic, and isolate sender behavior internally. The dedicated IP remains the clearest monetization layer, but it is not always the correct deliverability answer — and the most sophisticated platforms know this.
One concrete example worth noting: Brevo's default behavior for unauthenticated senders is to automatically reroute email through @brevosend.com rather than the sender's own domain. This makes custom domain authentication effectively mandatory on that platform, even though it carries no direct charge. It is the field's clearest illustration of the gap between "technically free" and "functionally required."
Read these as the operating implications for product, packaging, and pricing decisions — not as observations.
Across the providers surveyed, DKIM, SPF, and custom domain authentication are treated as standard onboarding functionality rather than premium infrastructure. It is considered table-stakes onboarding across the market. Charging for it would be a market anomaly and a conversion killer.
SendGrid ($30), Mailgun ($59), and Brevo ($21) all gate reputation isolation behind a paid IP. It remains one of the clearest and most defensible infrastructure monetization points in the stack — customers who have experienced shared pool deliverability issues arrive pre-convinced of the value.
Mailchimp halved limits twice in 2026. SendGrid removed its free plan entirely in 2025. Shared onboarding infrastructure is increasingly being constrained or monetized to accelerate upgrade pressure across the broader ESP market.
$3,000–$7,000 mandatory onboarding fees at Professional and Enterprise are unique to HubSpot in this set. No other platform charges for setup access — their primary mid-market lever alongside seat-based pricing.
Free tiers cap at 100–500 emails/day. Any campaign approaching meaningful voter or audience contact will hit these limits within days of ramp. The upgrade pressure is structurally embedded into modern ESP onboarding models.
Klaviyo and Omnisend are Shopify-native. Profile-based, engagement-driven billing is designed for e-commerce journeys — not the burst-send, event-driven cadence of political campaigns. A genuine market gap.