Resend · sdk · fg-0400

Email body shows [object Promise] after upgrading React Email

Recipients receive the literal text [object Promise]

Verified 2026-10-15 · Confirmed by 0 builders · Trust 50/100

Cause

render became async in @react-email/render 1.0.0 and renderAsync was removed in 2.0.0. Code that passes render() straight into html sends the Promise.

Fix

Await render, or pass the component through the react field and let the SDK render it.

Apply

const html = await render(<WelcomeEmail name={name} />); await resend.emails.send({ from, to, subject, html });

Affects: @react-email/render 1.0.0 and later (renderAsync removed in 2.0.0)

Sources

• https://github.com/resend/react-email/blob/canary/packages/render/CHANGELOG.md

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