Nitrosend vs Mailrelay.

Unlimited contacts, tracking on every plan, agent-native, and a published price at scale.

TL;DR

Mailrelay is a euro-priced email marketing platform with a free plan that carries 20,000 contacts and 80,000 emails a month, with no daily cap. Automations, A/B tests, segmentation, and heat-map reports come with it, and technical support by phone, chat, and ticket is attached to the free account too. If your list fits inside that, the argument is over and it's a good one.

Nitrosend specializes in email and prices on the emails you send, so contacts never enter the bill. Mailrelay bills on stored contacts and derives the month's email allowance from that tier at five emails per contact, which is why the decision arrives on the day 80,000 stops being enough. Mailrelay's API is broader than most people expect, covering campaigns, subscribers, transactional email, SMS, and ecommerce. It sits over a dashboard-first product, so an agent reaches it through somebody's wrapper. Ours is the surface the product is operated from, so the whole email stack answers to one agent command.

Teams sizing a list-priced plan against a send-priced one usually run the same numbers on Mailshake, MailSlurp, and Mailsoftly before they commit.

Pricing math

What you actually pay.

The two ladders are priced on different things. Mailrelay bills on stored contacts and derives the month's email allowance from that tier at five emails per contact, so the right-hand column names the contact tier that buys the send volume beside it. Nitrosend bills on emails sent. Mailrelay's figures are in euros and ours are in dollars.

Scenario	Nitrosend	Mailrelay
Free	8,000 emails to start, then 500/mo forever. Unlimited contacts, 1 seat, full MCP, API, and CLI	80,000 emails/mo to 20,000 contacts, free for as long as the account stays active, no daily cap, with phone, chat, and ticket support
Entry paid tier	$20 Pro: 20,000 emails, 3 seats, BYO sending and AI keys	€48 Standard: 100,000 emails to 20,000 contacts, priority queue and priority support. Open and click tracking isn't on this rung
~100,000 emails/mo	$100 Ultra: 125,000 emails, 5 brands, 10 seats. Contacts never enter the price	€67 Enterprise: the same 100,000 emails to 20,000 contacts, and open and click tracking comes back on this rung
500,000+ emails/mo	$300 Enterprise: 500K to 4M+ emails at a published price, with SSO and SAML	The ladder runs to 10,000,000 emails at 2,000,000 contacts, priced in the configurator

Prices accurate as of August 2026. Check vendor sites for current rates.

Migration

How to switch (or run both).

Nothing here is big-bang. Mailrelay keeps sending while you move, and the free account doesn't expire while you're using it, so the overlap can run as long as you want it to.

Add and verify your sending domain in Nitrosend. SPF and DKIM records sit alongside Mailrelay's, so both platforms can send from the same domain for as long as the overlap lasts.
Pull the list out one group at a time. Groups are Mailrelay's list primitive, and subscribers carry tags and custom fields, so groups map onto lists and custom fields onto custom fields when you import with nitro_import_contacts.
Take engagement history out of the campaign reports rather than the subscriber export. Clicks, impressions, opens, and unsubscribes are exposed per campaign, and that history is what a segment on the other side gets built from.
Rebuild autoresponders and RSS newsletters as flows with nitro_compose_flow. There's no flow object to port, so a sequence that lived as three separate autoresponders usually becomes one object for the first time.
Decide what carries your reputation. BYO sending keys on Pro and above route mail through Amazon SES, Resend, Postmark, Mailgun, or SendGrid, and Mailrelay's own pool isn't one of them, so a sender leaving its shared pool is warming a new path whichever platform it lands on. What travels with you is the domain and its authentication history.

Honest credit

What Mailrelay does well.

Picking a tool is about fit. Here's what Mailrelay is genuinely good at.

A free plan a real sender can run a business on: 20,000 contacts, 80,000 emails a month with no daily cap, for as long as the account stays active.
Automations and A/B tests come with the free plan rather than starting two tiers up.
Real-time reports with heat maps, from the free plan up.
Technical support by phone, chat, and ticket on every account, including the free one.
A REST API that covers the product: campaigns, subscribers, groups, senders, custom fields, transactional, SMS, WhatsApp, media, imports, and bounce management.
Ecommerce resources are in that API too, including stores, products, categories, and abandoned carts.
An SMTP relay alongside the API, for the systems that only speak SMTP.
RSS-to-newsletter automation, so a blog feed becomes a scheduled campaign with no build step.
Prepaid packs carry no subscriber limit, which suits a big list mailed rarely.

What Nitrosend adds

Where we think we're better.

Unlimited contacts on every plan, including Free, so a list that grows without being mailed never moves the bill.
We price on the emails you send, so 50,000 addresses mailed twice a month costs what the sending costs.
On Mailrelay the contact tier is also the send allowance, at five emails per contact per month.
On the subscription ladder, a small list mailed hard buys contact tiers it doesn't need.
Open and click tracking is on at every rung here, and it isn't a plan feature you can lose by moving down a tier.
Transactional email is part of the same product rather than a separate line on the bill.
A published price from 500,000 to over 4,000,000 emails a month, where the ladder usually turns into a configurator or a sales call.
MCP-first is an architecture, not an integration: every capability at Nitrosend is an API endpoint and an MCP tool before it's a screen.
Mailrelay's operator surface is a v1 REST API, so an agent reaches it through whatever wrapper somebody writes rather than through the platform.
BYO sending keys on Pro and above route your mail through Amazon SES, Resend, Postmark, Mailgun, or SendGrid, on the domain and IP you already warmed, which makes the move reversible.

Use case fit

When to pick which.

Pick Mailrelay if

Your list sits inside 20,000 contacts and you send inside 80,000 emails a month, so the whole thing is free and there's nothing to decide. It points the same way if you'd rather have a person on the phone than a ticket queue, and you want them in Spanish. A large list you mail a few times a year points there too, because a prepaid pack with no subscriber limit is the cheapest shape for it. So does wanting SMS or WhatsApp campaigns against the same contact record.

Pick Nitrosend if

Email is the channel your program runs on, you'd rather build against a documented email API than a dashboard, and you've crossed the free ceiling, so the question is what the next tier actually buys. It's the right call too when your list is much larger than your send volume, or much smaller than it, and you'd rather the bill tracked the sending either way. And it's right when you want the platform to answer to an agent end to end, including domain authentication, deliverability, billing, and the approval step that usually sends someone back to a dashboard.

Mailrelay vs Nitrosend - common questions.

Can Nitrosend replace Mailrelay?

For email, yes, and all of it answers to one agent command: campaigns, flows, segments, templates, contacts, and transactional sending, with transactional not a separate line on the bill. Mailrelay keeps the channels it was built for beyond email, so a team running SMS or WhatsApp campaigns against the same contact record either keeps it for those or splits the stack deliberately.

Is Nitrosend cheaper than Mailrelay?

Not at the bottom. Mailrelay's free plan carries 80,000 emails a month to 20,000 contacts, and ours carries 8,000 to start and then 500 a month. Mailrelay's entry paid rung is EUR 48 a month for 100,000 emails to 20,000 contacts. Nitrosend's Pro is USD 20 a month for 20,000 emails, with unlimited contacts. The two ladders are priced in different currencies and on different units, so it depends on volume: below 20,000 emails a month Pro is the smaller bill, and at 100,000 the Mailrelay rung buys more of them.

What happens when I outgrow Mailrelay's free plan?

You pick a contact tier, and the month's email allowance comes with it at five emails per contact. The first rung is 100,000 emails against the free plan's 80,000, and open and click tracking sits on Enterprise rather than Standard, so the upgrade decision is usually about reporting rather than volume.

Can I keep sending while I move?

Yes. Both platforms can authenticate against the same domain, so the overlap runs as long as you want it to and you move one message type at a time. Export by group while it runs, because groups map onto lists and custom fields onto custom fields. Engagement history is the part people miss, and it comes out of the campaign reports rather than the subscriber export.

Start with the free tier.

8,000 emails to start, then 500 a month, unlimited contacts, full MCP, API and CLI access. No credit card.