Partner Stories

Mastering Flushing in Business Central: Getting Consumption Right for Every Operation

Published by Insight Works

When production runs smoothly, consumption tracking often fades into the background. But when your actual usage doesn’t match what Business Central says it should, suddenly “flushing” becomes one of the most important topics on the shop floor.

Flushing — how Business Central records material consumption — affects everything: inventory accuracy, costing, WIP accounting, and even scheduling. The method you choose shapes how and when items are consumed from inventory. Get it wrong, and you’re chasing variances. Get it right, and you’re closing orders faster with cleaner data.

Let’s unpack how flushing works, where it gets tricky, and how Insight Works apps help manufacturers take control.

Forward vs. Backward Flushing in Business Central

The classic debate: forward flushing vs. backward flushing.

  • Forward flushing records material consumption at the start of an operation or production order. It’s great when you can predict exactly what will be used — common in repetitive or highly stable processes.
  • Backward flushing posts consumption automatically at completion. It’s simpler and faster for operators but assumes usage matches the BOM exactly.

In volatile environments — where scrap, substitutions, or shortages occur — backward flushing can introduce discrepancies. That’s where some manufacturers prefer to mix methods (e.g., backward flushing for fasteners, manual for high-cost components).

Manual Flushing: When Control Matters Most

For operations with high variability or strict traceability requirements, manual flushing remains the preferred method. You record consumption when you know it’s accurate — after inspection, quality checks, or when lots and serials are confirmed.

Business Central’s manual flushing consumption mode gives this control, and with recent 2025 Wave enhancements, you can now use “pick + manual flushing” without needing a warehouse pick document. That’s a big win for simpler operations that still demand accuracy.

Routing Link Codes: Tying Consumption to Operations

Precision starts with good structure. Routing link codes enable you to associate each BOM component with a specific routing operation. That means Business Central knows precisely when to trigger consumption — whether at setup, run time, or finish.

If you’re using flush by operation, consumption posts as each operation finishes rather than all at once. This not only improves reporting accuracy but also aligns better with Shop Floor Insight, where operators record progress in real time.

Advanced Scenarios: Lots, Substitutions, and Exceptions

Flushing isn’t always straightforward — especially when lot or serial tracking enters the mix. Business Central can’t automatically assign tracked lots during backward flushing, which means those items often need manual intervention.

The same goes for component substitutions. When you replace a BOM item midstream, your flushing logic doesn’t automatically update. That’s why many manufacturers rely on Enhanced Planning Pack or Shop Floor Insight to streamline these exception cases — ensuring every substitution or scrap adjustment flows correctly into production and costing.

Warehouse Picking and Flushing Integration

If you’re using Business Central’s Warehouse Management functionality, flushing ties directly into your picking and put-away process. When warehouse picks are posted, components can be automatically consumed — a crucial link between warehouse execution and production control.

Insight Works’ Warehouse Insight app takes this a step further: operators can pick, consume, and post production data from a mobile device in real time, reducing missed transactions and double entries.

The Costing Side: Inventory Valuation and WIP Impact

Flushing doesn’t just affect quantities — it affects inventory valuation and WIP accounting.

  • Forward flushing moves cost out of inventory earlier, impacting how WIP builds.
  • Backward flushing delays consumption until completion, meaning WIP may be understated mid-process.

Understanding these timing differences is critical for accurate reporting. If you’re running Shop Floor Insight or MxAPS, aligning flushing points with operation timing can help balance production efficiency with financial accuracy.

Setup and Troubleshooting Tips

Flushing begins with setup: you can define a flushing method right on the Item Card — Forward, Backward, Manual, or Pick+Manual. You can also override flushing per component directly on a production order line, which is especially useful for prototypes or MTO jobs.

Common errors include:

  • Missing routing link codes (system doesn’t know when to consume).
  • Items set to backward flush, but operations not reported as finished.
  • Components on manual flush with no consumption entry posted.

If you see messages like “Failed to flush consumption” or “Material not recorded,” it’s often due to these setup gaps — not a system bug.

Mixing Methods: Hybrid Flushing in the Real World

Manufacturers often mix manual and backward flushing in the same BOM — and that’s perfectly valid. Fasteners or low-cost materials may flush automatically, while expensive or critical components require manual verification.

The goal isn’t uniformity — it’s fit. Your flushing policy should align with your plant’s actual operations, not the other way around.

Best Practices for Flushing Policies

Here’s what the pros do:

  • Use routing link codes to align material usage with real-world operations.
  • Avoid full backward flushing for lot-tracked items.
  • Leverage Shop Floor Insight to post operation completions and trigger flushing accurately.
  • Periodically audit item settings — mismatched methods often cause hidden variances.
  • Keep an eye on Microsoft’s 2025 Wave updates for flushing enhancements (like simplified manual consumption).

Tailoring for Industry Scenarios

  • Make-to-Order (MTO): Manual or operation-based flushing provides the control needed for custom jobs.
  • Process or batch production: Backward flushing with operation-level triggers keeps consumption aligned with batch completions.
  • High-volume repetitive manufacturing: Forward flushing or hybrid approaches reduce manual entry and speed up order closeout.

Migrating from NAV to Business Central

If you’re upgrading from NAV, revisit your flushing policies. Business Central offers more granular control — including per-operation flushing, routing links, and better warehouse integration. Legacy settings often carry over, but small misalignments can create costing headaches if not reviewed.

Flushing Simplified: Apps that Make It Easier

Insight Works apps help manufacturers operationalize flushing logic:

Together, they help you execute consistent, accurate flushing policies that reflect how your plant really runs.

Closing Thought

Flushing isn’t just a setup choice — it’s a strategy. It shapes how you view costs, track materials, and feel about your production data. Whether you flush forward, backward, manually, or by operation, make sure your configuration mirrors your reality — and let the right Insight Works tools help you keep it that way.