Personalization (without helper) - Sending Two Different Emails to Two Different Groups of Recipients from two different From email address package main import ( "fmt" "log" "os" "github.com/sendgrid/sendgrid-go" ) func main() { request := sendgrid.GetRequest(os.Getenv("SENDGRID_API_KEY"), "/v3/mail/send", "https://api.sendgrid.com") request.Method = "POST" request.Body = []byte(`{ "personalizations": [{ "to": [{ "email": "[email protected]" }], "subject": "YOUR SUBJECT LINE GOES HERE" }, { "to": [{ "email": "[email protected]" }], "from": { "email": "[email protected]" }, "subject": "YOUR OTHER SUBJECT LINE GOES HERE" }], "from": { "email": "[email protected]" }, "content": [ { "type": "text/html", "value": "<p>Personalizations are awesome!</p>" } ] }`) response, err := sendgrid.API(request) if err != nil { log.Println(err) } else { fmt.Println(response.StatusCode) fmt.Println(response.Body) fmt.Println(response.Headers) } }