> Portal Navigation: > > - Append `.md` to any URL under `https://dev.wix.com/docs/` to get its markdown version. > - Pages are either content pages (article or reference text) or menu pages (a list of links to child pages). > - To get a menu page, truncate any URL to a parent path and append `.md` (e.g. `https://dev.wix.com/docs/sdk.md`, `https://dev.wix.com/docs/sdk/core-modules.md`). > - Top-level index of all portals: https://dev.wix.com/docs/llms.txt > - Full concatenated docs: https://dev.wix.com/docs/llms-full.txt ## Resource: Sample Flow ## Article: Sample Flow ## Article Link: https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/tax/tax-calculation-integration-service-plugin/sample-flow.md ## Article Content: # Sample Use Cases and Flows This article shares a possible use case your app could support, as well as a sample flow that could support the use case. You aren't limited to these exact flows, but it can be a helpful jumping off point as you plan your app's implementation. ## Calculate tax for the United Kingdom A business operating in the United Kingdom needs to charge and collect tax at different rates throughout the country. Your app can provide the correct tax to charge for their sales. Follow these steps to create an app that can calculate tax for the United Kingdom. 1. [Configure the service plugin](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/tax/tax-calculation-integration-service-plugin/introduction.md) and give it a `calculatorDisplayName`, such as `"UK Tax App"`. 1. Use [Tax Regions API](https://dev.wix.com/docs/rest/business-solutions/e-commerce/extensions/tax/tax-regions/introduction.md) to create or update tax regions for the UK with your app ID in the `appId` field. 1. Add logic to your app so that when Wix calls it with [Calculate Tax](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/tax/tax-calculation-integration-service-plugin/calculate-tax.md) your app returns a tax calculation based on different, relevant tax regions in [ISO-3166 alpha-2](https://en.wikipedia.org/wiki/ISO_3166-2) format. 1. \[Optional with REST\] You may also want to offer additional tax rates based on different categories of products. Use the [Tax Groups service plugin](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/tax/tax-groups-integration-service-plugin/configuration.md) to configure such tax groups.