# Collect customer phone numbers

Collect a phone number for shipping or invoicing when your customer makes a payment.

# Stripe-hosted page

> This is a Stripe-hosted page for when payment-ui is stripe-hosted. View the original doc at https://docs.stripe.com/payments/checkout/phone-numbers?payment-ui=stripe-hosted.

You can enable phone number collection on all `payment` and `subscription` [mode](https://docs.stripe.com/api/checkout/sessions/create.md#create_checkout_session-mode) Sessions (phone number collection isn’t supported in `setup` mode). Only collect phone numbers if you need them for the transaction.

## Enable phone number collection

To enable phone number collection, set [phone_number_collection[enabled]](https://docs.stripe.com/api/checkout/sessions/create.md#create_checkout_session-phone_number_collection-enabled) to `true` when creating a Checkout Session.

```dotnet
StripeConfiguration.ApiKey = "<<secret key>>";

var options = new Stripe.Checkout.SessionCreateOptions
{
    LineItems = new List<Stripe.Checkout.SessionLineItemOptions>
    {
        new Stripe.Checkout.SessionLineItemOptions
        {
            PriceData = new Stripe.Checkout.SessionLineItemPriceDataOptions
            {
                UnitAmount = 1000,
                ProductData = new Stripe.Checkout.SessionLineItemPriceDataProductDataOptions
                {
                    Name = "T-shirt",
                },
                Currency = "eur",
            },
            Quantity = 2,
        },
    },
    PhoneNumberCollection = new Stripe.Checkout.SessionPhoneNumberCollectionOptions
    {
        Enabled = true,
    },
    Mode = "payment",
    SuccessUrl = "https://example.com/success",
    CancelUrl = "https://example.com/cancel",
};
var service = new Stripe.Checkout.SessionService();
Stripe.Checkout.Session session = service.Create(options);
```

```go
stripe.Key = "<<secret key>>"

params := &stripe.CheckoutSessionParams{
  LineItems: []*stripe.CheckoutSessionLineItemParams{
    &stripe.CheckoutSessionLineItemParams{
      PriceData: &stripe.CheckoutSessionLineItemPriceDataParams{
        UnitAmount: stripe.Int64(1000),
        ProductData: &stripe.CheckoutSessionLineItemPriceDataProductDataParams{
          Name: stripe.String("T-shirt"),
        },
        Currency: stripe.String(string(stripe.CurrencyEUR)),
      },
      Quantity: stripe.Int64(2),
    },
  },
  PhoneNumberCollection: &stripe.CheckoutSessionPhoneNumberCollectionParams{
    Enabled: stripe.Bool(true),
  },
  Mode: stripe.String(string(stripe.CheckoutSessionModePayment)),
  SuccessURL: stripe.String("https://example.com/success"),
  CancelURL: stripe.String("https://example.com/cancel"),
};
result, err := session.New(params);
```

```java
Stripe.apiKey = "<<secret key>>";

SessionCreateParams params =
  SessionCreateParams.builder()
    .addLineItem(
      SessionCreateParams.LineItem.builder()
        .setPriceData(
          SessionCreateParams.LineItem.PriceData.builder()
            .setUnitAmount(1000L)
            .setProductData(
              SessionCreateParams.LineItem.PriceData.ProductData.builder()
                .setName("T-shirt")
                .build()
            )
            .setCurrency("eur")
            .build()
        )
        .setQuantity(2L)
        .build()
    )
    .setPhoneNumberCollection(
      SessionCreateParams.PhoneNumberCollection.builder().setEnabled(true).build()
    )
    .setMode(SessionCreateParams.Mode.PAYMENT)
    .setSuccessUrl("https://example.com/success")
    .setCancelUrl("https://example.com/cancel")
    .build();

Session session = Session.create(params);
```

```node
const stripe = require('stripe')('<<secret key>>');

const session = await stripe.checkout.sessions.create({
  line_items: [
    {
      price_data: {
        unit_amount: 1000,
        product_data: {
          name: 'T-shirt',
        },
        currency: 'eur',
      },
      quantity: 2,
    },
  ],
  phone_number_collection: {
    enabled: true,
  },
  mode: 'payment',
  success_url: 'https://example.com/success',
  cancel_url: 'https://example.com/cancel',
});
```

```python
import stripe
stripe.api_key = "<<secret key>>"

session = stripe.checkout.Session.create(
  line_items=[
    {
      "price_data": {"unit_amount": 1000, "product_data": {"name": "T-shirt"}, "currency": "eur"},
      "quantity": 2,
    },
  ],
  phone_number_collection={"enabled": True},
  mode="payment",
  success_url="https://example.com/success",
  cancel_url="https://example.com/cancel",
)
```

```php
$stripe = new \Stripe\StripeClient('<<secret key>>');

$session = $stripe->checkout->sessions->create([
  'line_items' => [
    [
      'price_data' => [
        'unit_amount' => 1000,
        'product_data' => ['name' => 'T-shirt'],
        'currency' => 'eur',
      ],
      'quantity' => 2,
    ],
  ],
  'phone_number_collection' => ['enabled' => true],
  'mode' => 'payment',
  'success_url' => 'https://example.com/success',
  'cancel_url' => 'https://example.com/cancel',
]);
```

```ruby
Stripe.api_key = '<<secret key>>'

session = Stripe::Checkout::Session.create({
  line_items: [
    {
      price_data: {
        unit_amount: 1000,
        product_data: {name: 'T-shirt'},
        currency: 'eur',
      },
      quantity: 2,
    },
  ],
  phone_number_collection: {enabled: true},
  mode: 'payment',
  success_url: 'https://example.com/success',
  cancel_url: 'https://example.com/cancel',
})
```

With phone number collection enabled, Checkout adds a _required_ phone number field to the payment form. If you’re collecting a shipping address, the phone number field displays under the address fields. Otherwise, Checkout displays the phone number field below the email input. Customers can only enter one phone number per session.

## Retrieve the phone number

When your customer checks out with third-party wallets, such as [Apple Pay](https://docs.stripe.com/apple-pay.md) or [Google Pay](https://docs.stripe.com/google-pay.md), the phone number format isn’t guaranteed because of limitations on those platforms. We return the phone number value that’s provided by the third-party wallet.

We guarantee phone numbers in the [E.164](https://en.wikipedia.org/wiki/E.164) format when a customer doesn’t use [wallet payments](https://docs.stripe.com/payments/wallets.md).

After the session, you can retrieve customer phone numbers from the resulting *Customer*, or *Checkout Session* objects:

- [On the Customer](https://docs.stripe.com/api/customers.md): Checkout saves collected phone numbers onto the [phone](https://docs.stripe.com/api/customers/object.md#customer_object-phone) property of the Customer object, which you can access programmatically by either fetching the Customer object directly with the [API](https://docs.stripe.com/api/customers/retrieve.md), or by listening for the [customer.created](https://docs.stripe.com/api/events/types.md#event_types-customer.created) event in a *webhook*. You can also view the customer’s phone number in the [dashboard](https://dashboard.stripe.com/customers).
- [On the Checkout Session](https://docs.stripe.com/api/checkout/sessions.md): The customer’s phone number is also saved in the [customer_details](https://docs.stripe.com/api/checkout/sessions/object.md#checkout_session_object-customer_details) hash of the Checkout Session object, under [customer_details.phone](https://docs.stripe.com/api/checkout/sessions/object.md#checkout_session_object-customer_details-phone). After each successful Checkout Session, Stripe emits the [checkout.session.completed](https://docs.stripe.com/api/events/types.md#event_types-checkout.session.completed) event containing the Checkout Session object (and phone number), which you can listen for in a *webhook*.

## Collect phone numbers for existing customers

Passing in an existing [Customer](https://docs.stripe.com/api/customers.md) with a populated [phone](https://docs.stripe.com/api/customers/object.md#customer_object-phone) property to the [Checkout Session](https://docs.stripe.com/api/checkout/sessions.md) results in the phone number field being prefilled.

If the customer updates their phone number, this updated value persists on the [phone](https://docs.stripe.com/api/checkout/sessions/object.md#checkout_session_object-phone) property on the [Customer object](https://docs.stripe.com/api/customers.md) , overwriting any previously saved phone number.

### Update phone numbers with the customer portal 

You can allow customers to manage their own accounts (which includes [updating their phone numbers](https://docs.stripe.com/api/customer_portal/configurations/create.md#create_portal_configuration-features-customer_update-allowed_updates)) in the customer portal.

## See Also

* [Integrate the customer portal](https://docs.stripe.com/customer-management.md)

# Embedded form

> This is a Embedded form for when payment-ui is embedded-form. View the original doc at https://docs.stripe.com/payments/checkout/phone-numbers?payment-ui=embedded-form.

You can enable phone number collection on all `payment` and `subscription` [mode](https://docs.stripe.com/api/checkout/sessions/create.md#create_checkout_session-mode) Sessions (phone number collection isn’t supported in `setup` mode). Only collect phone numbers if you need them for the transaction.

## Enable phone number collection

To enable phone number collection, set [phone_number_collection[enabled]](https://docs.stripe.com/api/checkout/sessions/create.md#create_checkout_session-phone_number_collection-enabled) to `true` when creating a Checkout Session.

```dotnet
StripeConfiguration.ApiKey = "<<secret key>>";

var options = new Stripe.Checkout.SessionCreateOptions
{
    LineItems = new List<Stripe.Checkout.SessionLineItemOptions>
    {
        new Stripe.Checkout.SessionLineItemOptions
        {
            PriceData = new Stripe.Checkout.SessionLineItemPriceDataOptions
            {
                UnitAmount = 1000,
                ProductData = new Stripe.Checkout.SessionLineItemPriceDataProductDataOptions
                {
                    Name = "T-shirt",
                },
                Currency = "eur",
            },
            Quantity = 2,
        },
    },
    PhoneNumberCollection = new Stripe.Checkout.SessionPhoneNumberCollectionOptions
    {
        Enabled = true,
    },
    Mode = "payment",
    UiMode = "embedded",
    ReturnUrl = "https://example.com/return",
};
var service = new Stripe.Checkout.SessionService();
Stripe.Checkout.Session session = service.Create(options);
```

```go
stripe.Key = "<<secret key>>"

params := &stripe.CheckoutSessionParams{
  LineItems: []*stripe.CheckoutSessionLineItemParams{
    &stripe.CheckoutSessionLineItemParams{
      PriceData: &stripe.CheckoutSessionLineItemPriceDataParams{
        UnitAmount: stripe.Int64(1000),
        ProductData: &stripe.CheckoutSessionLineItemPriceDataProductDataParams{
          Name: stripe.String("T-shirt"),
        },
        Currency: stripe.String(string(stripe.CurrencyEUR)),
      },
      Quantity: stripe.Int64(2),
    },
  },
  PhoneNumberCollection: &stripe.CheckoutSessionPhoneNumberCollectionParams{
    Enabled: stripe.Bool(true),
  },
  Mode: stripe.String(string(stripe.CheckoutSessionModePayment)),
  UIMode: stripe.String(string(stripe.CheckoutSessionUIModeEmbedded)),
  ReturnURL: stripe.String("https://example.com/return"),
};
result, err := session.New(params);
```

```java
Stripe.apiKey = "<<secret key>>";

SessionCreateParams params =
  SessionCreateParams.builder()
    .addLineItem(
      SessionCreateParams.LineItem.builder()
        .setPriceData(
          SessionCreateParams.LineItem.PriceData.builder()
            .setUnitAmount(1000L)
            .setProductData(
              SessionCreateParams.LineItem.PriceData.ProductData.builder()
                .setName("T-shirt")
                .build()
            )
            .setCurrency("eur")
            .build()
        )
        .setQuantity(2L)
        .build()
    )
    .setPhoneNumberCollection(
      SessionCreateParams.PhoneNumberCollection.builder().setEnabled(true).build()
    )
    .setMode(SessionCreateParams.Mode.PAYMENT)
    .setUiMode(SessionCreateParams.UiMode.EMBEDDED)
    .setReturnUrl("https://example.com/return")
    .build();

Session session = Session.create(params);
```

```node
const stripe = require('stripe')('<<secret key>>');

const session = await stripe.checkout.sessions.create({
  line_items: [
    {
      price_data: {
        unit_amount: 1000,
        product_data: {
          name: 'T-shirt',
        },
        currency: 'eur',
      },
      quantity: 2,
    },
  ],
  phone_number_collection: {
    enabled: true,
  },
  mode: 'payment',
  ui_mode: 'embedded',
  return_url: 'https://example.com/return',
});
```

```python
import stripe
stripe.api_key = "<<secret key>>"

session = stripe.checkout.Session.create(
  line_items=[
    {
      "price_data": {"unit_amount": 1000, "product_data": {"name": "T-shirt"}, "currency": "eur"},
      "quantity": 2,
    },
  ],
  phone_number_collection={"enabled": True},
  mode="payment",
  ui_mode="embedded",
  return_url="https://example.com/return",
)
```

```php
$stripe = new \Stripe\StripeClient('<<secret key>>');

$session = $stripe->checkout->sessions->create([
  'line_items' => [
    [
      'price_data' => [
        'unit_amount' => 1000,
        'product_data' => ['name' => 'T-shirt'],
        'currency' => 'eur',
      ],
      'quantity' => 2,
    ],
  ],
  'phone_number_collection' => ['enabled' => true],
  'mode' => 'payment',
  'ui_mode' => 'embedded',
  'return_url' => 'https://example.com/return',
]);
```

```ruby
Stripe.api_key = '<<secret key>>'

session = Stripe::Checkout::Session.create({
  line_items: [
    {
      price_data: {
        unit_amount: 1000,
        product_data: {name: 'T-shirt'},
        currency: 'eur',
      },
      quantity: 2,
    },
  ],
  phone_number_collection: {enabled: true},
  mode: 'payment',
  ui_mode: 'embedded',
  return_url: 'https://example.com/return',
})
```

With phone number collection enabled, Checkout adds a _required_ phone number field to the payment form. If you’re collecting a shipping address, the phone number field displays under the address fields. Otherwise, Checkout displays the phone number field below the email input. Customers can only enter one phone number per session.

## Retrieve the phone number

When your customer checks out with third-party wallets such as [Apple Pay](https://docs.stripe.com/apple-pay.md), or [Google Pay](https://docs.stripe.com/google-pay.md), the phone number format isn’t guaranteed because of limitations on those platforms. Checkout attempts to save phone numbers from third-party wallets in [E.164](https://en.wikipedia.org/wiki/E.164) format when possible. In all other cases, when a customer doesn’t use [Apple Pay](https://docs.stripe.com/apple-pay.md), or [Google Pay](https://docs.stripe.com/google-pay.md), we guarantee phone numbers in [E.164](https://en.wikipedia.org/wiki/E.164) format.

After the session, you can retrieve customer phone numbers from the resulting *Customer*, or *Checkout Session* objects:

- [On the Customer](https://docs.stripe.com/api/customers.md): Checkout saves collected phone numbers onto the [phone](https://docs.stripe.com/api/customers/object.md#customer_object-phone) property of the Customer object, which you can access programmatically by either fetching the Customer object directly with the [API](https://docs.stripe.com/api/customers/retrieve.md), or by listening for the [customer.created](https://docs.stripe.com/api/events/types.md#event_types-customer.created) event in a *webhook*. You can also view the customer’s phone number in the [dashboard](https://dashboard.stripe.com/customers).
- [On the Checkout Session](https://docs.stripe.com/api/checkout/sessions.md): The customer’s phone number is also saved in the [customer_details](https://docs.stripe.com/api/checkout/sessions/object.md#checkout_session_object-customer_details) hash of the Checkout Session object, under [customer_details.phone](https://docs.stripe.com/api/checkout/sessions/object.md#checkout_session_object-customer_details-phone). After each successful Checkout Session, Stripe emits the [checkout.session.completed](https://docs.stripe.com/api/events/types.md#event_types-checkout.session.completed) event containing the Checkout Session object (and phone number), which you can listen for in a *webhook*.

## Collect phone numbers for existing customers

Passing in an existing [Customer](https://docs.stripe.com/api/customers.md) with a populated [phone](https://docs.stripe.com/api/customers/object.md#customer_object-phone) property to the [Checkout Session](https://docs.stripe.com/api/checkout/sessions.md) results in the phone number field being prefilled.

If the customer updates their phone number, this updated value persists on the [phone](https://docs.stripe.com/api/checkout/sessions/object.md#checkout_session_object-phone) property on the [Customer object](https://docs.stripe.com/api/customers.md) , overwriting any previously saved phone number.

### Update phone numbers with the customer portal 

You can allow customers to manage their own accounts (which includes [updating their phone numbers](https://docs.stripe.com/api/customer_portal/configurations/create.md#create_portal_configuration-features-customer_update-allowed_updates)) in the customer portal.

## See Also

* [Integrate the customer portal](https://docs.stripe.com/customer-management.md)

# Embedded components

> This is a Embedded components for when payment-ui is embedded-components. View the original doc at https://docs.stripe.com/payments/checkout/phone-numbers?payment-ui=embedded-components.

You can enable phone number collection on all `payment` and `subscription` [mode](https://docs.stripe.com/api/checkout/sessions/create.md#create_checkout_session-mode) Checkout Sessions (phone number collection isn’t supported in `setup` mode). Only collect phone numbers if you need them for the transaction.

## Enable phone number collection

To enable phone number collection, set [phone_number_collection[enabled]](https://docs.stripe.com/api/checkout/sessions/create.md#create_checkout_session-phone_number_collection-enabled) to `true` when creating a Checkout Session.

```dotnet
StripeConfiguration.ApiKey = "<<secret key>>";

var options = new Stripe.Checkout.SessionCreateOptions
{
    LineItems = new List<Stripe.Checkout.SessionLineItemOptions>
    {
        new Stripe.Checkout.SessionLineItemOptions
        {
            PriceData = new Stripe.Checkout.SessionLineItemPriceDataOptions
            {
                UnitAmount = 1000,
                ProductData = new Stripe.Checkout.SessionLineItemPriceDataProductDataOptions
                {
                    Name = "T-shirt",
                },
                Currency = "eur",
            },
            Quantity = 2,
        },
    },
    PhoneNumberCollection = new Stripe.Checkout.SessionPhoneNumberCollectionOptions
    {
        Enabled = true,
    },
    Mode = "payment",
    UiMode = "custom",
    ReturnUrl = "https://example.com/return",
};
var service = new Stripe.Checkout.SessionService();
Stripe.Checkout.Session session = service.Create(options);
```

```go
stripe.Key = "<<secret key>>"

params := &stripe.CheckoutSessionParams{
  LineItems: []*stripe.CheckoutSessionLineItemParams{
    &stripe.CheckoutSessionLineItemParams{
      PriceData: &stripe.CheckoutSessionLineItemPriceDataParams{
        UnitAmount: stripe.Int64(1000),
        ProductData: &stripe.CheckoutSessionLineItemPriceDataProductDataParams{
          Name: stripe.String("T-shirt"),
        },
        Currency: stripe.String(string(stripe.CurrencyEUR)),
      },
      Quantity: stripe.Int64(2),
    },
  },
  PhoneNumberCollection: &stripe.CheckoutSessionPhoneNumberCollectionParams{
    Enabled: stripe.Bool(true),
  },
  Mode: stripe.String(string(stripe.CheckoutSessionModePayment)),
  UIMode: stripe.String(string(stripe.CheckoutSessionUIModeCustom)),
  ReturnURL: stripe.String("https://example.com/return"),
};
result, err := session.New(params);
```

```java
Stripe.apiKey = "<<secret key>>";

SessionCreateParams params =
  SessionCreateParams.builder()
    .addLineItem(
      SessionCreateParams.LineItem.builder()
        .setPriceData(
          SessionCreateParams.LineItem.PriceData.builder()
            .setUnitAmount(1000L)
            .setProductData(
              SessionCreateParams.LineItem.PriceData.ProductData.builder()
                .setName("T-shirt")
                .build()
            )
            .setCurrency("eur")
            .build()
        )
        .setQuantity(2L)
        .build()
    )
    .setPhoneNumberCollection(
      SessionCreateParams.PhoneNumberCollection.builder().setEnabled(true).build()
    )
    .setMode(SessionCreateParams.Mode.PAYMENT)
    .setUiMode(SessionCreateParams.UiMode.CUSTOM)
    .setReturnUrl("https://example.com/return")
    .build();

Session session = Session.create(params);
```

```node
const stripe = require('stripe')('<<secret key>>');

const session = await stripe.checkout.sessions.create({
  line_items: [
    {
      price_data: {
        unit_amount: 1000,
        product_data: {
          name: 'T-shirt',
        },
        currency: 'eur',
      },
      quantity: 2,
    },
  ],
  phone_number_collection: {
    enabled: true,
  },
  mode: 'payment',
  ui_mode: 'custom',
  return_url: 'https://example.com/return',
});
```

```python
import stripe
stripe.api_key = "<<secret key>>"

session = stripe.checkout.Session.create(
  line_items=[
    {
      "price_data": {"unit_amount": 1000, "product_data": {"name": "T-shirt"}, "currency": "eur"},
      "quantity": 2,
    },
  ],
  phone_number_collection={"enabled": True},
  mode="payment",
  ui_mode="custom",
  return_url="https://example.com/return",
)
```

```php
$stripe = new \Stripe\StripeClient('<<secret key>>');

$session = $stripe->checkout->sessions->create([
  'line_items' => [
    [
      'price_data' => [
        'unit_amount' => 1000,
        'product_data' => ['name' => 'T-shirt'],
        'currency' => 'eur',
      ],
      'quantity' => 2,
    ],
  ],
  'phone_number_collection' => ['enabled' => true],
  'mode' => 'payment',
  'ui_mode' => 'custom',
  'return_url' => 'https://example.com/return',
]);
```

```ruby
Stripe.api_key = '<<secret key>>'

session = Stripe::Checkout::Session.create({
  line_items: [
    {
      price_data: {
        unit_amount: 1000,
        product_data: {name: 'T-shirt'},
        currency: 'eur',
      },
      quantity: 2,
    },
  ],
  phone_number_collection: {enabled: true},
  mode: 'payment',
  ui_mode: 'custom',
  return_url: 'https://example.com/return',
})
```

## Collect the customer's phone number

Create a phone number input to collect your customer’s phone number. Call [updatePhoneNumber](https://docs.stripe.com/js/custom_checkout/update_phone_number) when your customer finishes the input to save the phone number.

Depending on the design of your checkout form, you can call `updatePhoneNumber` in the following ways:

* Directly before [submitting the payment](#submit-payment).
* Before transitioning to the next step, such as clicking a **Save** button, if your form includes multiple steps.

You’re responsible for validating and formatting phone numbers before calling `updatePhoneNumber`.

```html
<input type="tel" id="phone-number" />
```

```javascript
stripe.initCheckout({fetchClientSecret}).then((checkout) => {
  const phoneNumberInput = document.getElementById('phone-number');

  phoneNumberInput.addEventListener('blur', () => {
    checkout.updatePhoneNumber(phoneNumberInput.value);
  });
});
```

Create a component to collect your customer’s phone number. Call [updatePhoneNumber](https://docs.stripe.com/js/custom_checkout/update_phone_number) when your customer finishes the input to save the phone number.

Depending on the design of your checkout form, you can call `updatePhoneNumber` in the following ways:

* Directly before [submitting the payment](#submit-payment).
* Before transitioning to the next step, such as clicking a **Save** button, if your form includes multiple steps.

You’re responsible for validating and formatting phone numbers before calling `updatePhoneNumber`.

```jsx
import React from 'react';
import {useCheckout} from '@stripe/react-stripe-js';

const PhoneNumberInput = () => {
  const checkout = useCheckout();
  const [phoneNumber, setPhoneNumber] = React.useState('');

  const handleBlur = () => {
    checkout.updatePhoneNumber(phoneNumber);
  };

  const handleChange = (e) => {
    setPhoneNumber(e.target.value);
  };
  return (
    <div>
      <input
        type="text"
        value={phoneNumber}
        onChange={handleChange}
        onBlur={handleBlur}
      />
    </div>
  );
};

export default PhoneNumberInput;
```

## Retrieve the phone number

After the session, you can retrieve customer phone numbers from the resulting *Customer*, or *Checkout Session* objects:

- [On the Customer](https://docs.stripe.com/api/customers.md): Checkout saves collected phone numbers onto the [phone](https://docs.stripe.com/api/customers/object.md#customer_object-phone) property of the Customer object, which you can access programmatically by either fetching the Customer object directly with the [API](https://docs.stripe.com/api/customers/retrieve.md), or by listening for the [customer.created](https://docs.stripe.com/api/events/types.md#event_types-customer.created) event in a *webhook*. You can also view the customer’s phone number in the [dashboard](https://dashboard.stripe.com/customers).
- [On the Checkout Session](https://docs.stripe.com/api/checkout/sessions.md): The customer’s phone number is also saved in the [customer_details](https://docs.stripe.com/api/checkout/sessions/object.md#checkout_session_object-customer_details) hash of the Checkout Session object, under [customer_details.phone](https://docs.stripe.com/api/checkout/sessions/object.md#checkout_session_object-customer_details-phone). After each successful Checkout Session, Stripe emits the [checkout.session.completed](https://docs.stripe.com/api/events/types.md#event_types-checkout.session.completed) event containing the Checkout Session object (and phone number), which you can listen for in a *webhook*.