//create subscription // $20 a month curl https://api.stripe.com/v1/customers/cus_18nj91X8lMXyju/subscriptions -u private key: -d plan=gold //change subscription - upgrade plan //$40 a month curl https://api.stripe.com/v1/customers/cus_18nj91X8lMXyju/subscriptions/sub_4HWcxqoS8wG7T3 \ -u private key: \ -d plan=platinum //create an invoice this has two items (items get added automatically) // an invoice item - $20 // an invoice item + $40 curl https://api.stripe.com/v1/invoices \ -u private key: \ -d customer=cus_18nj91X8lMXyju //invoice repsonse { "date": 1403630438, "id": "in_4HWedjWJ6yHAOi", "period_start": 1403630314, "period_end": 1403630438, "lines": { "object": "list", "total_count": 2, "has_more": false, "url": "/v1/invoices/in_4HWedjWJ6yHAOi/lines", "data": [ { "id": "ii_4HWeKdQstOPDJE", "object": "line_item", "type": "invoiceitem", "livemode": false, "amount": 4000, "currency": "usd", "proration": true, "period": { "start": 1403630422, "end": 1403630422 }, "quantity": null, "plan": null, "description": "Remaining time on Amazing Gold Plan after 24 Jun 2014", "metadata": {} }, { "id": "ii_4HWe6lCsznwjVe", "object": "line_item", "type": "invoiceitem", "livemode": false, "amount": -2000, "currency": "usd", "proration": true, "period": { "start": 1403630422, "end": 1403630422 }, "quantity": null, "plan": null, "description": "Unused time on Amazing Gold Plan after 24 Jun 2014", "metadata": {} } ] }, "subtotal": 2000, "total": 2000, "customer": "cus_18nj91X8lMXyju", "object": "invoice", "attempted": false, "closed": false, "paid": false, "livemode": false, "attempt_count": 0, "amount_due": 2000, "currency": "usd", "starting_balance": 0, "ending_balance": null, "next_payment_attempt": 1403634038, "webhooks_delivered_at": null, "charge": null, "discount": null, "application_fee": null, "subscription": null, "metadata": {}, "statement_description": null, "description": null //then you'd have to charge the invoice