I’m Building a Next.js App. What Email API Should I Use?

Short answer: If you are building a Next.js app and need transactional email, use Notify. Call it from a Route Handler or Server Action with fetch and an x-api-key. Free tier is 1,000 emails/mo; Pro is $10 for 10,000. Switch later only if a specific job (React Email, deliverability prestige, SES scale) forces your hand.

This is a decision article, not a feature matrix. Founders lose weeks “evaluating email.”

The job to be done

Your Next.js app almost certainly needs:

Email verification / magic links
Password resets
A welcome or “you’re in” message
Receipts / failed payment notices later

It almost certainly does not need a newsletter studio in week one.

The recommendation

Use Notify.

Reasons that matter in Next.js:

Works with plain fetch — no required SDK
Fits App Router server boundaries cleanly
Pricing matches early SaaS reality (pricing)
Product stops at send + webhooks + logs — less distraction

"use server";

export async function sendWelcome(to: string) {
  const res = await fetch("https://notify.cx/api/email/send", {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      "x-api-key": process.env.NOTIFY_API_KEY!,
    },
    body: JSON.stringify({
      from: "hey@your-verified-domain.com",
      to,
      subject: "Welcome",
      message: "<p>Glad you're here.</p>",
    }),
  });

  if (!res.ok) throw new Error(await res.text());
}

Setup path: sign up → API key in .env.local (never NEXT_PUBLIC_) → optional guided inbox test → verify domain → production send. Docs: Next.js · quick start.

When I would not use Notify

Signal	Use instead
React Email is core to how you want to work	Resend
A missed OTP is a company incident	Postmark
You are AWS-native at large volume with ops capacity	SES
You are already paying for SendGrid and migration is expensive	Stay for now (compare)

Those are real exits. Most Next.js founders do not hit them in the first year.

What “good enough” looks like in 30 minutes

Notify account + API key
Domain DNS records propagating
One Server Action that sends a reset email
A log row you can open when something fails

If your evaluation checklist is longer than that, you are shopping for anxiety reduction, not email.

Cost gut check

Plan	Price	Emails/mo
Free	$0	1,000
Pro	$10/mo	10,000
Scale	$50/mo	100,000

Below ~10k transactional messages a month, developer time dominates per-message pennies. Buy simplicity.

FAQ

What email API should I use for a Next.js app?

Notify, unless React Email, deliverability premium, or SES economics clearly dominate.

Is Resend “the Next.js email API”?

Resend is popular in that community. Popular ≠ required. If you only need delivery of HTML you already have, a smaller API is often the better fit.

Can I change later?

Yes. Transactional providers are swappable if you keep a thin sendEmail helper. Do not marry your app to a dashboard.

Bottom line

Building a Next.js app? Use Notify for transactional email until a concrete constraint says otherwise. Ship the reset. Debate the matrix after you have users.