The quick answer
Go to Lists > Engineering > Engineering Change Order > New. Set the Subsidiary, ECO Type and Effective Start Date, then click Add BOM Changes and choose Replace, the old Item, the Item Replacement and one line per assembly BOM. Save the ECO, get it approved, then run Lists > Engineering > Implement Engineering Change Order. NetSuite creates a new BOM revision on each assembly that starts on the Effective Start Date and ends the old revision the day before.
The screenshots show sample data. Person and operating-company names are fictional. Use your own records and values when following the steps.
Before you start
You need the Engineering Change Order feature and Advanced Bill of Materials, an ECO type such as PC - Part Change, and assemblies whose BOMs have at least one revision that uses the component. If a BOM has no revisions, the accounting preference Allow ECOs to Modify BOMs Without Revisions decides whether an ECO can change it. Approval, field defaults and the implementation page depend on whether SuiteApprovals routes ECOs in your account, on OneWorld, and on your role and preferences, so some steps below can differ. The Approval Status and Next Approver may fill in on their own when a workflow is set up. This example replaces HW-440 Brass Hinge 40mm with HW-445 Stainless Hinge 40mm on CD-100 and TC-300, starting 11/02/2026.
01. Open a new ECO
From the Lists menu, point to Engineering, then Engineering Change Order, and choose New. The form has Primary Information and a Product Changes subtab with an empty Change Details list.
02. Describe the change and set approval
Select Alder Creek US in Subsidiary and PC - Part Change in ECO Type. Explain the reason in Description. Enter 11/02/2026 in Effective Start Date so the brass hinges already in stock are used first. Date already shows today. Set Approval Status to Pending Approval and choose the approver in Next Approver, unless your approval workflow fills them in for you.
03. Add the BOM changes
On Product Changes, click Add BOM Changes. Choose Replace in Action, HW-440 Brass Hinge 40mm in Item and HW-445 Stainless Hinge 40mm in Item Replacement. Click Add BOM Change and choose an Assembly Item and its BOM. Revision fills with the latest revision that uses the item, and New Revision proposes the next name. Both are suggestions you can change to fit your naming convention. Add a second line for the other assembly, then click Save. Save the change details before you pick a different Action or Item, because changing either can clear the lines. The replacement takes the replaced item's BOM quantity and component yield, so those cells are not editable for Replace.
04. Save the ECO
Click Save. In the demonstrated account, NetSuite says that change details with the same Action, Item and Replacement Item will be merged on save. Choose OK. The two assemblies sit under one Replace row in Change Details. Saving creates the record, here ECO 3, in Pending Approval.
05. Approve it
When SuiteApprovals routes the ECO, the Next Approver opens it and clicks Approve. In this example no workflow routes the ECO and the approver is its creator, so click Edit, set Approval Status to Approved and click Save. Approval only authorizes the change. No bill of materials has changed yet.
06. Implement it
From the Lists menu, point to Engineering and choose Implement Engineering Change Order. The page lists approved ECOs that start between Effective Date From and Effective Date To for the chosen Subsidiary. The default window runs 90 days from today. Click Mark All, then Implement.
NetSuite opens the ECO Implementation Status page. The new revisions are built in the background, so ECO 3 first reads Pending.
07. Confirm the new revisions
Click Refresh until Implementation Status reads Completed. If a change fails, the Error column explains why.
Then open the BOM, for example from Lists > Supply Chain > Bills of Materials, and look at Revisions. Door Rev B now ends on 11/01/2026 and the new Door Rev C starts on 11/02/2026 with no end date, so every date has exactly one revision.
Check the result
- The ECO reads Approved, and its Implementation Status reads Completed.
- Each affected BOM has a new revision that starts on the Effective Start Date of the ECO.
- The replaced revision ends the day before and the new revision has no end date.
- Open the new revision and confirm the replacement item takes the old item's place.
Common questions
Does approving an ECO change the bill of materials?
No. Approval authorizes the change. The BOM changes only when the ECO is implemented, either from Implement Engineering Change Order or automatically if the preference Implement Engineering Change Order Upon Final Approval is on.
How is an ECO normally approved?
With SuiteApprovals, the Next Approver opens the ECO and clicks Approve, and a rejection needs a reason. Setting Approval Status by hand, as in this example, is for ECOs that no workflow routes.
What do Revision and New Revision mean on a change line?
Revision is the existing BOM revision the change starts from. New Revision is the name of the revision NetSuite creates when the ECO is implemented.
Why did NetSuite say the change details will be merged?
Lines that share the same Action, Item and Replacement Item are one change. Saving the ECO merges them into one row in Change Details, with each assembly kept as its own line.
Why does the status say Pending?
Implementation runs in the background. Click Refresh on the ECO Implementation Status page until the status reads Completed. A failed change shows its error on the same page.
What dates does the new revision get?
The new revision starts on the Effective Start Date of the ECO. The revision it replaces ends the day before, unless it already ended earlier.
Can I add or remove a component with an ECO?
Yes. The Action choices in the Add BOM Changes window are Add, Remove and Replace. Each one creates a new revision from the revision you select.