Send emails with .NET

Learn how to send your first email using the Resend .NET SDK.

Prerequisites

To get the most out of this guide, you’ll need to:

• Create an API key
• Verify your domain

1. Install

dotnet CLI

dotnet add package Resend

2. Send emails using HTML

In the startup of your application, configure the DI container as follows:

using Resend;

builder.Services.AddOptions();
builder.Services.AddHttpClient<ResendClient>();
builder.Services.Configure<ResendClientOptions>( o =>
{
    o.ApiToken = Environment.GetEnvironmentVariable( "RESEND_APITOKEN" )!;
} );
builder.Services.AddTransient<IResend, ResendClient>();

Send an email using the injected IResend instance:

using Resend;

public class FeatureImplementation
{
    private readonly IResend _resend;


    public FeatureImplementation( IResend resend )
    {
        _resend = resend;
    }


    public Task Execute()
    {
        var message = new EmailMessage();
        message.From = "Acme <[e-mail]>";
        message.To.Add( "[e-mail]" );
        message.Subject = "hello world";
        message.HtmlBody = "<strong>it works!</strong>";

        await _resend.EmailSendAsync( message );
    }
}

3. Try it yourself

ASP.NET Controller API

See the full source code.

List of .NET examples (API, Web, HTML rendering, Async sending).