Line Item appearing Duplicate Tax Lines

Retired Boards Appdev Customers Discounts And Orders

Topic summary

A user is encountering duplicate tax lines appearing on order line items, despite not having a subscription app installed (which is typically the cause of this issue).

Key Details:

  • The order source is “web”
  • Tax lines array shows two identical entries with the same tax rate (0.1) and price (“0.90”)
  • Both tax entries have channel_liable: false and title “GST”

Current Status:

  • The issue is unexplained since the common cause (subscription apps) has been ruled out
  • No responses or solutions have been provided yet
  • The user is seeking help to understand why this duplication is occurring
Summarized with AI on November 19. AI used: claude-sonnet-4-5-20250929.
1

Hi all,

Why am I seeing tax_lines being duplicated when there should only be one? This happens usually when a subscription app is installed but I don’t have a subscription app installed in my case.

Order’s

"source_name":"web"

Affected Order Line Item (Redacted info)

{
                    "id": 00000000000000,
                    "admin_graphql_api_id": "gid://shopify/LineItem/33333333333333",
                    "name": "YYY",
                    "price": "9.00",
                    "product_exists": true,
                    "product_id": 2222222222222,
                    "quantity": 2,
                    "sku": "19487",
                    "taxable": true,
                    "title": "XXXXX",
                    "total_discount": "0.00",
                    "variant_id": 11111111111111,
                    "tax_lines": [
                        {
                            "channel_liable": false,
                            "price": "0.90",
                            "rate": 0.1,
                            "title": "GST"
                        },
                        {
                            "channel_liable": false,
                            "price": "0.90",
                            "rate": 0.1,
                            "title": "GST"
                        }
                    ]
}