Abandoned checkouts - Hosted checkout

TL;DR: No signal ever arrives when a shopper simply leaves — the session stays pending until it expires. Cancel it proactively, or reconcile by polling after the TTL.

A shopper closing the tab, navigating away, or clicking their browser’s back button doesn’t send any signal to your server — the session simply stays pending until it expires.

When this happens

The shopper closes the tab or browser before entering payment details.
The shopper clicks back or navigates to another site mid-checkout.
In embedded mode, the shopper navigates your own page away from the iframe.

What you see

Signal	Value
Redirect	None — the shopper’s browser never returns to `success_url` or `cancel_url`
Embedded event	None — closing or navigating away doesn’t post a `CHECKOUT_*` message
Session status	Stays `pending` until the TTL elapses, then moves to `expired`
Webhook	None

What to do

Don't wait on a redirect or event that will never arrive

There’s no signal from the shopper’s browser for this case — build your own UX around a timeout on your side (for example, “we didn’t hear back — did you complete your purchase?”) rather than waiting indefinitely.

Optionally cancel the session proactively

If your own UI detects the shopper has left (for example, they started a new checkout for the same cart), cancel the still-pending session explicitly instead of waiting for it to expire (API reference):

#!/usr/bin/env bash
# Merchant-initiated cancel (X-Api-Key, not CSRF/customer-driven). Idempotent
# while pending; 409 if already processing or terminal.
set -euo pipefail

CHECKOUT_BASE="${RADIUMONE_CHECKOUT_BASE:-https://checkout-sandbox.radiumone.io}"
: "${RADIUMONE_SECRET_KEY:?set RADIUMONE_SECRET_KEY to your r1sk_* secret key}"
: "${RADIUMONE_CHECKOUT_ID:?set RADIUMONE_CHECKOUT_ID to the session to cancel}"

curl -sS -X POST "$CHECKOUT_BASE/api/v1/checkout/sessions/$RADIUMONE_CHECKOUT_ID/cancel" \
  -H "X-Api-Key: $RADIUMONE_SECRET_KEY"

#!/usr/bin/env node
// Merchant-initiated cancel (X-Api-Key, not CSRF/customer-driven). Idempotent
// while pending; 409 if already processing or terminal. Node 18+ ESM fetch.
// Env: RADIUMONE_SECRET_KEY, RADIUMONE_CHECKOUT_ID, RADIUMONE_CHECKOUT_BASE.
const CHECKOUT_BASE = process.env.RADIUMONE_CHECKOUT_BASE || "https://checkout-sandbox.radiumone.io";
const secretKey = process.env.RADIUMONE_SECRET_KEY;
const checkoutId = process.env.RADIUMONE_CHECKOUT_ID;

async function cancelCheckoutSession() {
  const res = await fetch(`${CHECKOUT_BASE}/api/v1/checkout/sessions/${checkoutId}/cancel`, {
    method: "POST",
    headers: { "X-Api-Key": secretKey },
  });
  const payload = await res.json();
  if (!res.ok) {
    // 409 session:invalid_state if already processing/terminal.
    throw new Error(`checkout session cancel failed: ${payload.code ?? payload.type} (${res.status})`);
  }
  return payload;
}

cancelCheckoutSession().then((r) => console.log(JSON.stringify(r, null, 2)));

#!/usr/bin/env python3
"""Merchant-initiated cancel (X-Api-Key, not CSRF/customer-driven). Idempotent
while pending; 409 if already processing or terminal.
"""
import json
import os

import requests

CHECKOUT_BASE = os.environ.get("RADIUMONE_CHECKOUT_BASE", "https://checkout-sandbox.radiumone.io")


def cancel_checkout_session() -> dict:
    checkout_id = os.environ["RADIUMONE_CHECKOUT_ID"]
    resp = requests.post(
        f"{CHECKOUT_BASE}/api/v1/checkout/sessions/{checkout_id}/cancel",
        headers={"X-Api-Key": os.environ.get("RADIUMONE_SECRET_KEY", "")},
        timeout=30,
    )
    payload = resp.json()
    if not resp.ok:
        # 409 session:invalid_state if already processing/terminal.
        code = payload.get("code") or payload.get("type")
        raise RuntimeError(f"checkout session cancel failed: {code} ({resp.status_code})")
    return payload


if __name__ == "__main__":
    print(json.dumps(cancel_checkout_session(), indent=2))

Reconcile by polling after the TTL, if you don't cancel proactively

Otherwise, check the session’s status after its TTL has elapsed:

#!/usr/bin/env bash
# Authenticated merchant view of a checkout session. Branch on data.status;
# never on gateway_response_code. Note: GET timestamps are epoch
# milliseconds, unlike the ISO string returned at create time.
set -euo pipefail

CHECKOUT_BASE="${RADIUMONE_CHECKOUT_BASE:-https://checkout-sandbox.radiumone.io}"
: "${RADIUMONE_SECRET_KEY:?set RADIUMONE_SECRET_KEY to your r1sk_* secret key}"
: "${RADIUMONE_CHECKOUT_ID:?set RADIUMONE_CHECKOUT_ID to the checkout_id to verify}"

curl -sS "$CHECKOUT_BASE/api/v1/checkout/sessions/$RADIUMONE_CHECKOUT_ID" \
  -H "X-Api-Key: $RADIUMONE_SECRET_KEY"

#!/usr/bin/env node
// Authenticated merchant view of a checkout session. Branch on data.status;
// never on gateway_response_code. Node 18+ ESM fetch.
// Env: RADIUMONE_SECRET_KEY, RADIUMONE_CHECKOUT_ID, RADIUMONE_CHECKOUT_BASE.
const CHECKOUT_BASE = process.env.RADIUMONE_CHECKOUT_BASE || "https://checkout-sandbox.radiumone.io";
const secretKey = process.env.RADIUMONE_SECRET_KEY;
const checkoutId = process.env.RADIUMONE_CHECKOUT_ID;

async function retrieveCheckoutSession() {
  const res = await fetch(`${CHECKOUT_BASE}/api/v1/checkout/sessions/${checkoutId}`, {
    headers: { "X-Api-Key": secretKey },
  });
  const payload = await res.json();
  if (!res.ok) {
    throw new Error(`checkout session fetch failed: ${payload.code ?? payload.type} (${res.status})`);
  }
  // Confirm order_reference and amount match your order before fulfilling.
  return payload;
}

retrieveCheckoutSession().then((r) => console.log(JSON.stringify(r, null, 2)));

#!/usr/bin/env python3
"""Authenticated merchant view of a checkout session. Branch on ``status``;
never on ``gateway_response_code``.
"""
import json
import os

import requests

CHECKOUT_BASE = os.environ.get("RADIUMONE_CHECKOUT_BASE", "https://checkout-sandbox.radiumone.io")


def retrieve_checkout_session() -> dict:
    checkout_id = os.environ["RADIUMONE_CHECKOUT_ID"]
    resp = requests.get(
        f"{CHECKOUT_BASE}/api/v1/checkout/sessions/{checkout_id}",
        headers={"X-Api-Key": os.environ.get("RADIUMONE_SECRET_KEY", "")},
        timeout=30,
    )
    payload = resp.json()
    if not resp.ok:
        code = payload.get("code") or payload.get("type")
        raise RuntimeError(f"checkout session fetch failed: {code} ({resp.status_code})")
    # Confirm order_reference and amount match your order before fulfilling.
    return payload


if __name__ == "__main__":
    print(json.dumps(retrieve_checkout_session(), indent=2))

A status of expired confirms nothing was charged. If you need to prompt the shopper to try again, see Handle expired checkout sessions.

Redirect integration

The full redirect-mode flow.

Embed hosted checkout

The full embedded-mode flow.

Handle expired checkout sessions

What happens once the TTL elapses.

Handle failures

All ten failure scenarios, symptom → page.

Introduction

Guides

3D Secure

Handle failures

Errors

Reference

Abandoned checkouts - Hosted checkout

When this happens

What you see

What to do

Redirect integration

Embed hosted checkout

Handle expired checkout sessions

Handle failures

​When this happens

​What you see

​What to do

​Related

Redirect integration

Embed hosted checkout

Handle expired checkout sessions

Handle failures

When this happens

What you see

What to do

Related