const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

fetch('https://api.thanks.io/api/v2/sub-accounts', options)
  .then(response => response.json())
  .then(response => console.log(response))
  .catch(err => console.error(err));

{
  "data": [
    {
      "id": 7,
      "user_id": 2,
      "title": "Test Sub Account",
      "return_name": "Your Business",
      "return_address": "123 Main Street",
      "return_address2": "Apartment 1",
      "return_city": "Fake City",
      "return_state": "NY",
      "return_postal_code": "55555",
      "default_envelope": null,
      "created_at": "2020-03-26 17:44:31",
      "updated_at": "2020-03-31 02:12:07"
    }
  ]
}