If you send your SMS from the website, you will be taken to a confirmation page after you’ve sent your message. On that page you’ll see if the message was sent and to whom.
If you send your SMS from your Smartphone application, you’ll see “Message sent!” and the SMS charge will be visible on your Call History.
If you send your SMS from your mobile to our local US Rebtel number, you’ll see the SMS charge on your Account History.