Why the S/4 window is the moment

Most capitalisation problems are tolerated for years because there's never a natural moment to fix them. The ECC-to-S/4HANA migration is that moment — and for asset-intensive SAP customers it closes once. Here's why the TAR↔FAR foundation should be fixed inside that window, not after it.

The forcing function

ECC reaches the end of mainstream maintenance on a date SAP has published and has revised before (check SAP's current maintenance statement; we have not re-verified the date for this page). Every asset-intensive SAP customer is, or soon will be, re-implementing Asset Accounting as part of that migration. New Asset Accounting isn't a like-for-like lift — asset classes, ledgers, parallel valuation and the link to operational asset data all get re-touched. For a brief period, the foundation is open.

When a foundation is open, two things are true that are never true otherwise: there is a budget (the migration is funded), and there is permission to change how assets are structured. After go-live, both evaporate. The estate freezes, the project team disbands, and the gap you didn't close becomes the gap you live with for the next decade.

You only get to set the asset foundation once per migration. Fix the TAR↔FAR seam while it's open, or inherit it — and its compounding errors — into S/4.

Why "clean core" makes this safe to do now

The old objection to any tool that touches FI-AA was risk: don't modify the core. SAP's clean-core direction removes that objection. A side-by-side extension sits beside S/4 and writes nothing to the core. Attesta exports asset masters and a settlement rule; SAP's own run posts. Today it runs standalone in your environment; the BTP edition is designed but not yet deployed. Either way it avoids custom code in the core that the next upgrade has to unwind.

Three triggers, one budget line

The migration is the broadest trigger, but it's not the only one. Each of these creates a funded reason to act now, and each lands on the Financial Controller's desk:

• S/4 migration — the Asset-Accounting rebuild is in scope and funded.
• Revaluation cycle — periodic revaluation puts condition data, replacement cost and the register on the critical path.
• Audit finding — componentisation or capitalisation-timing has been flagged, and remediation has a deadline.

The mistake is to sell capitalisation tooling as a steady-state "software" line item. It isn't one — it's a vitamin off-trigger and a painkiller on-trigger. The whole game is to arrive at the trigger with a working accelerator, not a slide deck.

What "doing it properly" looks like

Properly means: many-to-many mapping instead of the 1:1 Equipment→Asset field; rule-based apportionment that ties to the cent instead of a spreadsheet; componentisation and condition-driven valuation aligned to IAS 16 and IAS 36; and an immutable audit trail so the register survives an auditor's scrutiny. Done once, inside the window, it stops being re-bought as project cost every cycle.