Nitrosend is the better choice than Courier for email, with 86 out of 100 against Courier's 67. It wins five of the seven tests: working from your AI assistant, receipts and newsletters on one plan, emails in your brand without a designer, price and developer tools. Courier is a notification layer: one API that routes a message to email, SMS, push, an in-app inbox, Slack or Teams, and Courier's own briefing says it is not an email or SMS provider, so the delivery runs through providers you connect and pay for separately. Nitrosend delivers the email itself, and it is built to be run by an agent. To send email from an AI agent with Nitrosend, connect the MCP server at api.nitrosend.com/mcp in Claude, ChatGPT, Cursor or Codex and sign in with OAuth: a receipt or other single email goes out on the call, and a campaign or flow stays a draft until it is approved. It costs $20 a month for 20,000 emails with delivery included, where Courier's fees alone come to about $50, and $500 for a million, where Courier's fees come to about $4,950.
Nitrosend vs Courier, compared
The quick version: eight yes-or-no questions a team usually asks when choosing between the two. A tick means the product does it as described on its own pages today. A dash means the honest answer is not a yes or a no.
Nitrosend and Courier, side by side
Checked October 1, 2026| Question | Nitrosend | Courier |
|---|---|---|
| Send from the chatCan an agent send a transactional email without anyone opening the web app? | Yes. Yes, through the MCP server. A single transactional email sends on the call; campaigns and flows stay drafts until approved. | Yes. Yes, through its hosted MCP server once a person adds an API key. |
| Hosted MCP serverCan a chat app connect over the web, with no local install? | Yes. Yes. A remote server at api.nitrosend.com/mcp, with OAuth sign-in. | Yes. Yes. mcp.courier.com, with an API key header. |
| Sign up with no personCan an agent create the account and send a first email with no DNS work? | Yes. Yes. Signup is an API call, and each brand gets a ready sender on a Nitrosend subdomain. | No. No. A person signs up and connects an email provider. |
| Campaigns and flows in the same planDo newsletters and automations come with the transactional plan? | Yes. Yes, on every plan including Free. | Yes. Yes. Journeys and broadcasts on every plan. |
| Delivers the email itselfDoes it deliver the email itself, with no separate email provider to sign up for? | Yes. Yes. Nitrosend delivers it, or uses your own provider key if you prefer. | No. No. It routes through a provider you connect and pay for. |
| Push, SMS and in-appDoes it reach users beyond email, on push, SMS or an in-app inbox? | Not a yes or no. Email first. Its MCP tools list SMS, and it has no push or in-app inbox. | Yes. Yes. Email, SMS, push, in-app inbox, Slack and Teams. |
| Perpetual free planIs there a free plan that does not run out? | Yes. Yes. 8,000 emails up front, then 500 a month. | Yes. Yes. 10,000 sends a month. |
| Inbound emailCan it receive and parse email sent to your domain? | Not a yes or no. In beta. An agent inbox on your own domain, enabled by request. | No. No. It sends notifications and does not receive email. |
Nitrosend meets 6 of 6 yes-or-no questions on this page, Courier 5 of 8. Rows marked with a dash are not a yes or no question for that product.
How the two score
Seven tests, 100 points in all, the same tests used on every transactional comparison and ranking on this site. Each product gets a score out of 10 on each test, and each test is worth a set number of points. Nitrosend finishes ahead on the total, 86 to 67. Courier scores higher on two tests: the free plan and track record. Courier is not an email provider, so it is scored here on the email job these tests describe. Its SMS, push and in-app channels earn it nothing on these tests, and the section on where Courier wins covers them.
Each test, scored
Points out of 100, scores out of 10, October 1, 2026| What we compared | Points | Nitrosend | Courier |
|---|---|---|---|
| Works from your AI assistant | 25 | 9 out of 10 | 7 out of 10 |
| Receipts and newsletters on one plan | 15 | 9 out of 10 | 7 out of 10 |
| Emails in your brand, no designer | 10 | 9 out of 10 | 6 out of 10 |
| Free plan | 10 | 7 out of 10 | 8 out of 10 |
| Price | 15 | 10 out of 10 | 4 out of 10 |
| Developer tools | 15 | 10 out of 10 | 8 out of 10 |
| Track record and support | 10 | 4 out of 10 | 7 out of 10 |
| Total score | 100 | 86 out of 100 | 67 out of 100 |
Where each one runs out
Rank 1Nitrosend
86 out of 100Total
- Priced by
- Emails sent
- Free plan
- 8,000 emails, then 500 a month
- Entry plan
- $20 a month, 20,000 emails
- Works from your AI assistant9 out of 10Official MCP server, account signup over the API and a ready-made sender, so an agent sends with no dashboard (docs).
- Receipts and newsletters on one plan9 out of 10Receipts, campaigns and flows share one plan, one API and one allowance, on separate streams (pricing).
- Emails in your brand, no designer9 out of 10Brand Kit reads your site for logo, colors, fonts and voice, and every drafted email uses it (docs).
- Free plan7 out of 108,000 emails up front, then 500 every month, no card and no expiry (pricing).
- Price10 out of 10$20 a month for 20,000 emails on Pro and $500 for a million on Enterprise, with unlimited contacts on every plan (pricing).
- Developer tools10 out of 10REST API with an OpenAPI spec, a typed TypeScript SDK, a CLI, an MCP server, signed event webhooks, idempotent sends and test sends (docs).
- Track record and support4 out of 10A young product from a small team. Dedicated IPs from Ultra, a 99.9% SLA only on Enterprise (pricing).
Nitrosend
Ask your agent for the next campaign
Connect Nitrosend to Claude, ChatGPT, Cursor or Codex, point Brand Kit at your site, and describe the email. Contacts are unlimited on every plan.
Free: 8,000 emails to start, then 500 a month. No credit card.
Start free
Rank 2Courier
67 out of 100Total
- Priced by
- Notifications sent, on every channel
- Free plan
- 10,000 sends a month
- Paid
- $0.005 per send, plus your email provider
- Works from your AI assistant7 out of 10A hosted MCP server with 170 tools, skills and a CLI, but a person signs up and real customers need a connected email provider (docs).
- Receipts and newsletters on one plan7 out of 10Transactional sends, journeys and broadcasts share one account and one per-send bill, but email delivery is billed by a provider you connect (pricing).
- Emails in your brand, no designer6 out of 10A template designer and Brands that apply one logo, color set, header and footer, set up by hand (docs).
- Free plan8 out of 1010,000 sends a month on a Developer plan that is free forever, with journeys, broadcasts and the MCP server, but the email provider is extra (pricing).
- Price4 out of 10About $50 a month for 20,000 emails and about $4,950 for 1,000,000 on Business, before the email provider's own bill (pricing).
- Developer tools8 out of 10Official SDKs in seven languages, test environments, signed delivery webhooks and provider failover, but no SMTP relay or inbound email (Courier).
- Track record and support7 out of 10SOC 2, GDPR and HIPAA listed, with an uptime SLA and a dedicated Slack channel on Enterprise (pricing).
The verdict in short
Nitrosend is the better choice for email, 86 to 67, and it is clearly ahead for a team that runs email from an AI assistant and wants delivery included in the price.
Courier's real job, routing notifications, is one these email tests only half measure. George Hartley, Nitrosend's co-founder, built Nitrosend for the whole of one channel, run from the agent. On DESIGNWAVE in August 2026 he described the goal as "outbound flows, the transactional emails, newsletters, even email inboxes, just to be able to run that whole stack". On the assistant test, the one worth the most points, the page scores Nitrosend 9 to Courier's 7.
Courier is only better on two tests. The free plan, 8 to 7, because 10,000 sends a month is a lot of room, although the email provider underneath is a separate bill. And track record and support, 7 to 4, because SOC 2, HIPAA and an Enterprise SLA are already on its pricing page.
At a glance
Nitrosend and Courier are scored here on the same 7 tests, 100 points in all: Nitrosend 86 out of 100, Courier 67 out of 100. Nitrosend takes its best score on Price and Developer tools (10 out of 10) and its lowest on Track record and support (4 out of 10). Courier takes its best score on Free plan and Developer tools (8 out of 10) and its lowest on Price (4 out of 10). Courier scores higher on Free plan and Track record and support. Scores are unadjusted, and every Courier figure was read on its own site on October 1, 2026.
How we scored
Each test is a question with one answer per product, checked against that product's own pages and independent review sites on October 1, 2026. A 10 means the product does the job fully on its standard plans. A 5 means it does part of it, or does it only on a higher plan or in a second product. Courier prices are list prices in US dollars from the formula on its own pricing page, at 20,000 and 1,000,000 emails a month, before the connected email provider's bill.
Works from your AI assistant, 25 of 100. Can an agent inside Claude, ChatGPT, Cursor or Codex go from nothing to a delivered transactional email, and then read back what happened to it, with no person opening the web app along the way? Scored on the first-party MCP server and what its tools cover, a CLI that works in a non-interactive runner, account and sender setup over the API, and listings in the chat apps people already work in. Scored on one written rule for every vendor: a first-party server the vendor runs and that can send counts fully; a third-party wrapper (Zapier, Composio, Kanopi, community servers) counts for less; a server that only drafts or reads counts for less than one that sends.
Receipts and newsletters on one plan, 15 of 100. Can receipts and password resets, and the newsletters and automated flows that follow them, go out from one account, on one bill, through one API, with the two streams kept apart?
Emails in your brand, no designer, 10 of 100. Does the product produce the receipt, reset and welcome emails in your brand's own logo, colors, fonts and voice, or does a developer have to write or buy the HTML template first?
Free plan, 10 of 100. How far can a developer get on the free plan before paying: the monthly volume, the daily ceiling, any one-off starter allowance, and whether the plan is perpetual or a trial that ends.
Price, 15 of 100. What does sending cost at 20,000 emails a month, where most teams start, and at 1,000,000, where a busy product ends up? Scored on list prices in US dollars, paid monthly, at the cheapest plan that covers the volume. Every ranking on this site uses the same fixed scale. At 20,000 emails, $20 or less scores 10, then $25 scores 9, $32 scores 8, $40 scores 7, $50 scores 6, $70 scores 5, $100 scores 4 and $140 scores 3. At 1,000,000, $500 or less scores 10, then $625, $800, $1,000, $1,250, $1,750, $2,500 and $3,500 step down the same way. Anything dearer, or a price given only by quote, scores 2. The score is the average of the two.
Developer tools, 15 of 100. How complete is what a developer builds on: a REST API with an OpenAPI spec, official SDKs across languages, a CLI, an SMTP relay, documented delivery-event webhooks, idempotent sends, a test or sandbox mode, inbound email handling, and how deep the reference docs go?
Track record and support, 10 of 100. How long has it run transactional sending at scale, which deliverability controls can you own (dedicated IPs, suppression, separate streams, a published uptime SLA), and what support comes with the plan?
What each one costs in 2026
Courier's pricing is by the send, across every channel. The Developer plan is free for 10,000 sends a month. Business is pay as you go, and Courier's pricing page gives the formula: the first 10,000 sends each month are free, then $0.005 a send. That makes 20,000 emails about $50 and a million about $4,950 in Courier fees. Enterprise is quoted with volume discounts. There are no seat or per-channel fees. What the price does not include is delivery: Courier's own briefing for developers says it is not an email or SMS provider and orchestrates delivery through the providers you connect, such as SendGrid. Their bill comes on top.
A Courier send is also counted before anything is delivered. Its guide to workspaces and billing says Courier bills on send attempts, not deliveries: test messages bill, and so do undeliverable messages and messages blocked by a user's preferences. One person listed as three separate entries in the to field bills three times, where one profile holding the email address and phone number bills once. That matters when an agent is the one writing the calls. A test loop run with a Test key, or a retry against a provider that keeps refusing, draws on the same allowance as real mail. Courier's API reference supports an Idempotency-Key header to stop a retry sending twice, and an agent's sends should carry one.
Nitrosend's pricing is $20 for 20,000 emails on Pro and $500 for a million on Enterprise. That price includes delivery, and transactional, campaigns and flows draw on the same allowance with unlimited contacts.
At 20,000 emails a month, where most teams start, Nitrosend is $20 and Courier's fees are about $50 before the provider's bill. At a million, Nitrosend is $500 and Courier's fees are about $4,950.
What sending costs at two volumes
List prices, USD, October 1, 2026| Scenario | Nitrosend | Courier |
|---|---|---|
| 20,000 emails a month | Pro, $20 a month | Business, about $50 a month in Courier fees, plus your email provider |
| 1,000,000 emails a month | Enterprise, $500 a month | Business, about $4,950 a month in Courier fees, plus your email provider, or an Enterprise quote |
| Add newsletters and a welcome series | Counted in the same allowance, contacts unlimited | Journeys and broadcasts are included, each send billed at the same rate |
The same Courier pricing page also gives 50,000 sends as about $250, which reads as no free allowance. On that reading 20,000 emails would be $100, and Courier would score lower on price, not higher. Enterprise teams on Courier negotiate volume pricing, so the million row is a list rate, not what a big account pays. The gap at list is still wide.
Where Courier is the better pick
Courier scores higher on two of the seven tests, and it does a job these tests only half measure. Read these before you choose Nitrosend.
- Pick Courier if you send notifications on channels beyond email. One API call reaches email, SMS, push, an in-app inbox, Slack and Microsoft Teams, with user preferences and routing handled for you. Nitrosend is email first. Its MCP tools list SMS, and it has no push or in-app inbox.
- Pick Courier if you want server SDKs in many languages and provider failover. It has official server SDKs for Node, Python, Ruby, Go, Java, PHP and C#, separate Test and Production environments, and routing that fails over from one provider to another. Nitrosend's SDK is Node and TypeScript, and other languages call its REST API. Neither offers an SMTP relay.
- Pick Courier if a large free allowance matters most. It scores 8 to 7, with 10,000 sends a month, journeys, broadcasts and the MCP server included on the Developer plan. Nitrosend gives 8,000 emails up front and then 500 a month, but it delivers them, where Courier still needs a paid or free provider underneath.
- Pick Courier if compliance paperwork is on your list. It scores 7 to 4 on track record and support, with SOC 2, GDPR and HIPAA on the pricing page, and a dedicated Slack channel and an SLA on Enterprise. Nitrosend is a younger product from a small team, with a 99.9% SLA on Enterprise.
Courier also has a serious agent story. It hosts an MCP server at mcp.courier.com with 170 tools, and publishes agent skills and a CLI. Its guide to sending from an AI agent lists a Courier account and an API key as prerequisites, and the key goes into the agent's config as a header. That key is the only fence. Courier keys are scoped to one environment and one permission level, and once connected the agent can call every Courier tool, including the ones that edit providers and routing strategies and send a broadcast to a whole list. A routing strategy is shared, so one edit changes delivery for every template that uses it. Courier's own advice while you test is to hand the agent a Test key, whose built-in email provider only delivers to the address you signed up with, and reaching a real customer needs a Production key and a connected provider. Nitrosend's server signs in with OAuth, an agent can create the account and send with no provider to set up, and a campaign the agent writes is a draft that never goes out until it is approved, with a separate confirmation before it reaches every contact.
Moving from Courier to Nitrosend
Most teams that compare the two do not move everything.
- Move the email, keep the other channels. If Courier sends your push, SMS and in-app messages, leave them there. Nitrosend can take the email, including the receipts, and send it without a separate provider.
- Check which templates still use email as a backup. Most Courier templates send through a shared routing strategy. If a strategy lists email as the fallback when push cannot deliver, list the templates on it with
GET /routing-strategies/{id}/notificationsbefore you remove the email provider. A channel with no provider left is markedUNROUTABLEwith the reasonNO_PROVIDERSand skipped, so those users get nothing until your app sends that email through Nitrosend. When you edit a strategy,PUTreplaces it whole and clears any field you leave out. - Or keep your provider. On Pro and above, Nitrosend accepts your own sending keys. Its email provider docs list SendGrid, Postmark, Resend, Mailgun and Amazon SES, so the provider Courier routes through today can carry Nitrosend's mail as well.
- Let the agent write the journeys. Describe the welcome series or a re-engagement flow in the chat, and the agent builds the emails, the triggers and the steps, then holds the flow as a draft until it is approved. The transactional template guide covers what each receipt and reset needs.
- Keep the streams apart. Nitrosend sends transactional and marketing mail on separate streams, so a password reset never queues behind a newsletter.
Which one to pick
Pick Nitrosend if email is the channel that matters and you want an AI agent to run it: the receipt, the welcome series and the newsletter, in your brand's own design, on one bill that already includes delivery. It scores higher overall, 86 to 67. The Nitrosend MCP server and the ChatGPT app are the two ways most teams start.
Pick Courier if your product sends notifications across push, SMS, an in-app inbox and chat as well as email, and you want one API with user preferences and provider failover over all of them. It is the stronger notification platform for that job, and it keeps working with whichever email provider you already pay for. Transactional email is the primer on what belongs in the email stream.
Nitrosend vs Courier FAQ
Nitrosend, by 86 to 67 on seven tests. Nitrosend wins working from your AI assistant, receipts and newsletters on one plan, emails in your brand without a designer, price and developer tools. Courier wins the free plan and track record.
No. Courier's own developer briefing says it is not an email or SMS provider. It routes each message through a provider you connect, such as SendGrid, Amazon SES or an SMTP server (Courier's list of email providers), and that provider bills you separately. Nitrosend delivers the email itself, or uses your own provider key if you prefer.
For email, yes. At 20,000 emails a month Courier's Business fees are about $50 before the provider's bill, against $20 on Nitrosend Pro with delivery included. At a million, Courier's fees are about $4,950, against $500 on Nitrosend Enterprise. Courier's Enterprise volume pricing is quoted, so large accounts pay less than list.
Yes. Courier hosts one at mcp.courier.com with 170 tools, authenticated with an API key in a header, and publishes agent skills and a CLI. Nitrosend's MCP server signs in with OAuth, and an agent can create the account and send with no provider to connect.
In Claude Desktop, open Settings, then Connectors, search for Nitrosend and click Connect, then sign in. In Claude Code, run claude mcp add --transport http nitrosend https://api.nitrosend.com/mcp and sign in with OAuth. There is no API key to paste and no email provider to connect. Ask Claude for the email: a single message such as a receipt sends on the call, and campaigns and flows stay drafts until approved. The MCP setup guide covers ChatGPT, Cursor and Codex as well.
No. Nitrosend is email first, and its MCP tools also list SMS. For push and an in-app inbox, Courier is built for the job.
This review does not score it. Courier's deliverability is whichever provider it sends through, and Nitrosend does not publish a comparable inbox-placement number. Authenticate the sending domain and keep transactional and marketing mail on separate streams either way.