# custom calculation formula for line items **URL:** \ **Category:** Tips, Tricks & Best Practices\ **Tags:** how-to\ **Created:** [February 4, 2026, 4:13pm UTC](https://community.hubspot.com/t/custom-calculation-formula-for-line-items/145825 "2026-02-04T16:13:10Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Ribe90](https://d10pqhm3lwygmk.cloudfront.net/user_avatar/community.hubspot.com/ribe90/32/75082_2.png) [@Ribe90](https://community.hubspot.com/u/Ribe90)\ **Post date:** [February 4, 2026, 4:13pm UTC](https://community.hubspot.com/t/custom-calculation-formula-for-line-items/145825/1 "2026-02-04T16:13:10Z")
Thanks to the new update, I created a custom calculation property for line items to calculate the unit price after applying a percentage discount. The formula used is: (unit price - (unit price \* (unit discount / 100))) When testing the property, the calculation works correctly. However, when I add this property in the line item section during quote creation, the calculation does not work as expected: it only works if the discount is entered as an absolute number rather than a percentage. This behavior seems inconsistent, since the property test returns the correct result. ---
**Author:** ![RNoll](https://d10pqhm3lwygmk.cloudfront.net/user_avatar/community.hubspot.com/rnoll/32/70782_2.png) [@RNoll](https://community.hubspot.com/u/RNoll)\ **Post date:** [February 4, 2026, 7:49pm UTC](https://community.hubspot.com/t/custom-calculation-formula-for-line-items/145825/2 "2026-02-04T19:49:59Z")
Fair warning, I just used Hub Helper Harry, a HubSpot-related GPT, to find this answer. It suggested replacing “unit discount” with “discount\_percentage”, since apparently **u**** nit discount **= a** currency amount.** It recommends changing your formula to: **unit\_price \* (1 - (discount\_percentage / 100))**. So if you wanted to give someone a 10% discount, in the discount\_percentage property: - You enter 10. - HubSpot _ **displays** _ it as **10%** - Under the hood, the value is still just 10, though, which is why you still need to divide by 100. I hope this helps. Robyn ---
**Author:** ![Ribe90](https://d10pqhm3lwygmk.cloudfront.net/user_avatar/community.hubspot.com/ribe90/32/75082_2.png) [@Ribe90](https://community.hubspot.com/u/Ribe90)\ **Post date:** [February 5, 2026, 9:55am UTC](https://community.hubspot.com/t/custom-calculation-formula-for-line-items/145825/3 "2026-02-05T09:55:28Z")
Thanks so much Robyn for your help ---
**Author:** ![Ribe90](https://d10pqhm3lwygmk.cloudfront.net/user_avatar/community.hubspot.com/ribe90/32/75082_2.png) [@Ribe90](https://community.hubspot.com/u/Ribe90)\ **Post date:** [February 5, 2026, 2:47pm UTC](https://community.hubspot.com/t/custom-calculation-formula-for-line-items/145825/4 "2026-02-05T14:47:57Z")
@RNoll Now everything works, thank you very much. However, I’m having a new problem. When I try to insert it into the estimate template, I can’t find it even though I used it in the estimate construction table. Any suggestions? ---
**Author:** ![RNoll](https://d10pqhm3lwygmk.cloudfront.net/user_avatar/community.hubspot.com/rnoll/32/70782_2.png) [@RNoll](https://community.hubspot.com/u/RNoll)\ **Post date:** [February 5, 2026, 4:07pm UTC](https://community.hubspot.com/t/custom-calculation-formula-for-line-items/145825/5 "2026-02-05T16:07:28Z")
Just FYI, this was generated by Hub Helper Harry again. Our company does not use the Sales Hub or Quotes. Here’s its response: Yes — this is expected behavior in HubSpot, and it’s **not related to the formula** anymore. ## What’s happening There are **two different contexts** in HubSpot, and they behave differently: 1. **Quote editor (estimate construction table)** 2. **Estimate / quote template** So even though the property: - Exists - Calculates correctly - Is already used on the estimate …it will **not appear in the template** unless the line item table itself is customized. This is a **template limitation** , not a calculation issue. * * * ## Why you can’t find the property in the template The most common reasons are: ### 1. The template uses the default line item table The default table: - Supports only a predefined set of standard fields - Does not surface custom line item properties ### 2. The property is custom (calculated or not) This is expected behavior. Custom line item properties **do not appear by default** in templates unless the table is custom-configured. ### 3. The template was created before the property existed In some cases, templates don’t refresh available fields automatically. Re-adding the line item table or duplicating the template can help. * * * ## What to do next (practical steps) ### Option A — Use a custom line item table (recommended) In the quote template editor: - Remove the default line item table - Insert a **custom line item table** - Manually add the calculated property as a column This is the **only reliable way** to surface custom line item calculations. * * * ### Option B — Use an existing supported field If the number must appear on quotes but **not necessarily as its own column** : - Map the value into a supported field (e.g., unit price or total) - Let HubSpot render it automatically Less flexible, but simpler. * * * If you want, tell me: - Your Sales Hub tier - Whether this is a **quote** or **estimate** template - Whether you’re using the default or custom line item table it can give you exact click-by-click steps. I hope that helps! Robyn