Subscription Products

Update multiple properties of a subscription line item

Comprehensive endpoint for updating a subscription line item’s quantity, price, product variant, and/or selling plan in a single API call. Changes are applied intelligently - only modified values trigger updates.

Key Features:

Update any combination of: quantity, price, variant, or selling plan
Intelligent change detection - only updates what’s different
Automatic handling of prepaid subscription pricing
Preserves existing discount cycles when updating price
Partial success allowed - some updates may fail while others succeed
Each change creates separate activity log entries

Prepaid Subscription Handling: For prepaid subscriptions (billing interval > delivery interval):

When isPricePerUnit=true: Price is multiplied by interval ratio
Example: Monthly billing, weekly delivery = price × 4
When isPricePerUnit=false: Price is used as total billing amount

Update Process:

Validates line item exists in the subscription
Calculates interval multiplier for prepaid logic
Updates in order: selling plan → price → quantity → variant
Each update uses separate Shopify GraphQL mutation
Failures are logged but don’t block other updates

Selling Plan Updates:

Can update by ID or name (name takes precedence)
Only updates if different from current plan
Useful for changing delivery frequency options

Price Updates:

Preserves existing discount cycles (up to 2 cycles)
Recalculates cycle discounts based on new base price
Triggers shipping price recalculation
Sends price update email to customer

Quantity Updates:

Validates against min/max quantity rules
Updates Build-a-Box totals if applicable
May trigger discount recalculations

Variant Updates:

Changes the product itself (different SKU)
Validates new variant exists and is available
May affect pricing and discounts

Important Notes:

All parameters except contractId and lineId are optional
Provide only the values you want to change
Price is always in shop’s base currency
Changes apply to future orders only

Authentication: Requires valid X-API-Key header

PUT

api

external

subscription-contracts-update-line-item

Update multiple properties of a subscription line item

curl --request PUT \
  --url https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item \
  --header 'X-API-Key: <x-api-key>'

import requests

url = "https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item"

headers = {"X-API-Key": "<x-api-key>"}

response = requests.put(url, headers=headers)

print(response.text)

const options = {method: 'PUT', headers: {'X-API-Key': '<x-api-key>'}};

fetch('https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

const url = 'https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item';
const options = {method: 'PUT', headers: {'X-API-Key': '<x-api-key>'}};

fetch(url, options)
  .then(res => res.json())
  .then(json => console.log(json))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "PUT",
  CURLOPT_HTTPHEADER => [
    "X-API-Key: <x-api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item"

	req, _ := http.NewRequest("PUT", url, nil)

	req.Header.Add("X-API-Key", "<x-api-key>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

require 'uri'
require 'net/http'

url = URI("https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Put.new(url)
request["X-API-Key"] = '<x-api-key>'

response = http.request(request)
puts response.read_body

{
  "billingPolicy": {
    "interval": "MONTH",
    "intervalCount": 1
  },
  "deliveryPolicy": {
    "interval": "WEEK",
    "intervalCount": 1
  },
  "id": "gid://shopify/SubscriptionContract/123456789",
  "lines": {
    "edges": [
      {
        "node": {
          "currentPrice": {
            "amount": "119.97",
            "currencyCode": "USD"
          },
          "id": "gid://shopify/SubscriptionLine/111111",
          "pricingPolicy": {
            "basePrice": {
              "amount": "9.99",
              "currencyCode": "USD"
            },
            "cycleDiscounts": [
              {
                "adjustmentType": "PERCENTAGE",
                "adjustmentValue": {
                  "percentage": 10
                },
                "afterCycle": 3,
                "computedPrice": {
                  "amount": "107.97",
                  "currencyCode": "USD"
                }
              }
            ]
          },
          "quantity": 3,
          "sellingPlanId": "gid://shopify/SellingPlan/777777",
          "sellingPlanName": "Deliver every week",
          "title": "Premium Coffee - Medium Roast",
          "variantId": "gid://shopify/ProductVariant/98765432101"
        }
      }
    ]
  },
  "nextBillingDate": "2024-03-01T00:00:00Z",
  "status": "ACTIVE"
}

Headers

X-API-Key

string

required

API Key for authentication

Query Parameters

contractId

integer<int64>

required

Subscription contract ID

Required range: x >= 1

api_key

string

API Key (Deprecated - Use X-API-Key header instead)

quantity

integer

New quantity for the line item. Leave unchanged if not updating quantity.

Required range: 1 <= x <= 9999

variantId

string

New product variant ID in Shopify GID format (e.g., gid://shopify/ProductVariant/42549172011164). This updates the associated product. Leave this parameter blank if you are not switching products.

lineId

string

required

Line item ID to update. Must be the full GraphQL ID including gid:// prefix

price

number<double>

New price for the line item in shop currency. Behavior depends on isPricePerUnit flag.

Required range: 0.01 <= x <= 999999.99

isPricePerUnit

boolean

default:false

Determines how price is interpreted for prepaid subscriptions:

true: Price is per unit (per delivery), will be multiplied by interval ratio
false: Price is total billing amount (for all deliveries in billing period)

Example: Monthly billing, weekly delivery, price=$10

isPricePerUnit=true: Customer pays $40/month ($10 × 4 weeks)
isPricePerUnit=false: Customer pays $10/month total

sellingPlanName

string

Name of the selling plan to apply. Takes precedence over current selling plan. Used to change delivery frequencies.

Maximum string length: 255

Response

Line item successfully updated

billingAttempts

object

Show child attributes

billingPolicy

object

Show child attributes

createdAt

object

customAttributes

object[]

Show child attributes

customer

object

Show child attributes

customerPaymentMethod

object

Show child attributes

deliveryMethod

object

Show child attributes

deliveryPolicy

object

Show child attributes

deliveryPrice

object

Show child attributes

discounts

object

Show child attributes

get__typename

string

lastPaymentStatus

enum<string>

Available options:

SUCCEEDED,

FAILED,

$UNKNOWN

lines

object

Show child attributes

nextBillingDate

object

note

string

originOrder

object

Show child attributes

revisionId

object

status

enum<string>

Available options:

ACTIVE,

PAUSED,

CANCELLED,

EXPIRED,

FAILED,

$UNKNOWN

updatedAt

object

Update multiple properties of a subscription line item

curl --request PUT \
  --url https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item \
  --header 'X-API-Key: <x-api-key>'

import requests

url = "https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item"

headers = {"X-API-Key": "<x-api-key>"}

response = requests.put(url, headers=headers)

print(response.text)

const options = {method: 'PUT', headers: {'X-API-Key': '<x-api-key>'}};

fetch('https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

const url = 'https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item';
const options = {method: 'PUT', headers: {'X-API-Key': '<x-api-key>'}};

fetch(url, options)
  .then(res => res.json())
  .then(json => console.log(json))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "PUT",
  CURLOPT_HTTPHEADER => [
    "X-API-Key: <x-api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item"

	req, _ := http.NewRequest("PUT", url, nil)

	req.Header.Add("X-API-Key", "<x-api-key>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

require 'uri'
require 'net/http'

url = URI("https://subscription-admin.appstle.com/api/external/v2/subscription-contracts-update-line-item")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Put.new(url)
request["X-API-Key"] = '<x-api-key>'

response = http.request(request)
puts response.read_body

{
  "billingPolicy": {
    "interval": "MONTH",
    "intervalCount": 1
  },
  "deliveryPolicy": {
    "interval": "WEEK",
    "intervalCount": 1
  },
  "id": "gid://shopify/SubscriptionContract/123456789",
  "lines": {
    "edges": [
      {
        "node": {
          "currentPrice": {
            "amount": "119.97",
            "currencyCode": "USD"
          },
          "id": "gid://shopify/SubscriptionLine/111111",
          "pricingPolicy": {
            "basePrice": {
              "amount": "9.99",
              "currencyCode": "USD"
            },
            "cycleDiscounts": [
              {
                "adjustmentType": "PERCENTAGE",
                "adjustmentValue": {
                  "percentage": 10
                },
                "afterCycle": 3,
                "computedPrice": {
                  "amount": "107.97",
                  "currencyCode": "USD"
                }
              }
            ]
          },
          "quantity": 3,
          "sellingPlanId": "gid://shopify/SellingPlan/777777",
          "sellingPlanName": "Deliver every week",
          "title": "Premium Coffee - Medium Roast",
          "variantId": "gid://shopify/ProductVariant/98765432101"
        }
      }
    ]
  },
  "nextBillingDate": "2024-03-01T00:00:00Z",
  "status": "ACTIVE"
}

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Update multiple properties of a subscription line item

Headers

Query Parameters

Response