Ops & Supply

How to audit inventory shrinkage as CPG Founders

Ops & SupplyFor CPG Founders3 apps11 steps~22 min to set up

Inventory shrinkage in CPG doesn't announce itself — it bleeds out slowly through co-packer overages, 3PL receiving discrepancies, FBA inbound shortages, and distributor deductions that never quite match your ship quantities. You're reconciling a QuickBooks bill against a co-packer invoice against a 3PL receiving report, all in separate spreadsheets, usually a month after the shrinkage already happened. By the time you catch that Lot 2024-0847 came back 200 units short from your 3PL, the product may already be sold, expired, or written off. Most CPG founders discover shrinkage during year-end inventory counts or when a retailer audit surfaces something. Neither is a good time.

Build this on Starch → See the apps used

Ops & SupplyFor CPG Founders3 apps11 steps~22 min to set up

Outcome

What you'll set up

A live shrinkage dashboard that pulls your Plaid bank transactions, co-packer invoices, and 3PL receiving reports into one view so you can see the gap between what you paid to produce and what actually landed in sellable inventory — by lot, by location, and by SKU.

Automated anomaly alerts that flag when a vendor charge (3PL storage, co-packer overage fee, FBA disposal) deviates from its historical baseline, so you catch a $3,000 charge that should be $300 before it disappears into your P&L.

A lot-level audit trail that lets you run a mock shrinkage reconciliation in minutes — tracing every unit from production order through co-packer delivery, 3PL inbound, and outbound shipment — so you're ready when an SQF auditor or retail buyer asks for your shrinkage rate.

The Starch recipe

Apps, data, and prompts

The combination of Starch apps, the data sources they pull from, and the prompts you use to drive them.

Apps used

Transaction Insights Lot Tracker Inventory Planner

Data sources & config

Transaction Insights connects to Plaid as a scheduled-sync provider — Starch syncs your bank transaction data on a schedule so every co-packer payment, 3PL storage bill, and FBA disposal fee is visible in one place without manual exports. Lot Tracker (currently in development — request beta access) will wire into your co-packer and 3PL receiving records to give you one-up-one-down lot-level chain of custody. Inventory Planner (also in development — request beta access) will connect across your warehouse, 3PL, and FBA locations. For any co-packer or 3PL portal that doesn't have an API, Starch automates it through your browser — no API needed.

Prompts to copy

Connect my Plaid accounts and show me every transaction tagged to co-packer payments, 3PL fees, and FBA disposal charges for the last 90 days. Flag any charge from those vendors that's more than 20% above their 90-day average.

Build me a shrinkage reconciliation view that compares units ordered from my co-packer, units received at my 3PL by lot number, and units delivered to FBA or my wholesale accounts. Show the variance by SKU and highlight any lot where units received is more than 2% below units ordered.

Set up a recurring weekly alert: every Monday, show me any new vendor that charged my bank account in the last 7 days that hasn't charged me in the prior 60 days. I want to know about unexpected charges before they hit my QuickBooks.

Run these in Starch → or paste them into your favorite agent

Walkthrough

Step-by-step

1 Connect your business bank accounts through Plaid. Starch syncs your transaction data on a schedule — every co-packer invoice payment, 3PL receiving fee, and FBA disposal charge shows up categorized automatically.

2 Open Transaction Insights and tell Starch which vendor categories to watch: 'Show me all transactions tagged to co-packer payments and 3PL fees for the last 6 months, grouped by vendor, with month-over-month variance.' This becomes your baseline.

3 Set up anomaly alerts for your top shrinkage sources. Tell Starch: 'Alert me any time a 3PL storage or disposal charge from [your 3PL name] is more than 25% above the trailing 60-day average for that vendor.' You'll get flagged before the discrepancy becomes a habit.

4 Pull your co-packer production orders and delivery confirmations. If your co-packer uses a portal you can log into, Starch automates it through your browser — no API needed — to pull the batch quantities and lot numbers from each production run.

5 Map your 3PL receiving reports against those production order quantities by lot. Tell Starch: 'Compare the units shipped from my co-packer by lot number to the units received at my 3PL. Show me every lot where the receiving quantity is more than 1% below the ship quantity.' This is where most silent shrinkage surfaces.

6 Extend the reconciliation to your outbound channels. Compare 3PL outbound shipment quantities to FBA inbound receipts, and 3PL pick-and-ship quantities to distributor invoice quantities. Shrinkage at this stage often appears as FBA inbound shortages that Amazon marks as 'damaged' without documentation.

7 When Lot Tracker launches (request beta access now), import your historical lot data and establish your one-up-one-down chain of custody going forward. Every production batch gets tracked from your co-packer through your 3PL to the end customer, with FSMA 204-compliant Key Data Elements captured automatically.

8 Run a mock shrinkage audit quarterly. Tell Starch: 'Show me the full chain of custody for every unit of Lot 2025-0312 — from production order through co-packer delivery, 3PL receiving, and outbound shipment. Flag any unit count gaps at each handoff.' This is the same drill an SQF auditor or retail buyer will run on you.

9 Connect QuickBooks from Starch's integration catalog (the agent queries it live) to cross-reference your shrinkage write-offs against your Plaid-tracked vendor payments. If you're writing off inventory in QuickBooks that you can't trace to a documented loss event, that's a gap worth closing.

10 Set up a monthly shrinkage report. Tell Starch: 'Every first Monday of the month, generate a shrinkage summary showing: units ordered vs. units received vs. units sold by SKU, total dollar value of unexplained variance, and any vendor charges that don't have a corresponding receiving discrepancy to explain them. Send it to me in Slack.' Starch syncs your Slack data to deliver it — no manual pull required.

11 Use the anomaly history to build distributor dispute documentation. When a distributor deducts for short shipments, pull the lot-level chain of custody showing the units left your 3PL in full. That's your dispute evidence — ready in minutes instead of days.

See this running on Starch

Connect your tools, describe what you want, and the agent builds it. Closed beta is free.

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Worked example

Q1 2026 Shrinkage Audit — Oat-Based Snack Brand, 3 SKUs

Sample numbers from a real run

Co-packer production order — 8,400 units (3 SKUs)	29,400
3PL receiving confirmation — 8,217 units received	28,720
FBA inbound receipts — 3,100 units (vs. 3,280 shipped)	10,850
FBA disposal charges — Lot 2026-0114, 'damaged inbound'	1,260
Unexplained shrinkage variance (co-packer to 3PL)	2,380
FBA inbound shortage — filed reimbursement claim	1,890

In Q1 2026, this three-SKU oat snack brand ran its first Starch-powered shrinkage audit after noticing their co-packer bills and QuickBooks inventory counts weren't adding up. Transaction Insights flagged two things immediately: a $1,260 FBA disposal charge from Amazon on Lot 2026-0114 that was double the prior quarter's disposal average, and a co-packer payment in February that was $800 above the monthly baseline with no corresponding increase in units received. Starch pulled the co-packer portal data through browser automation (the co-packer uses an online production portal — no API) and compared it against the 3PL receiving report: 183 units short across two lots, worth $2,380 at landed cost. The FBA inbound shortage on the same lot added another 180 units — a $1,890 variance Amazon had marked as 'damaged inbound' without supporting documentation. Total Q1 shrinkage identified: $5,530 across co-packer delivery loss, FBA inbound shortage, and disposal charges. The brand filed an FBA reimbursement claim with the lot-level documentation and recovered $1,650. The co-packer discrepancy is now a standing agenda item on their monthly production review call. Before Starch, this audit would have taken two days of spreadsheet reconciliation — and probably still missed the disposal charge anomaly.

Measurement

How you'll know it's working

Shrinkage rate by SKU (units lost as % of units produced, tracked by lot)

Co-packer delivery variance (units ordered vs. units received at 3PL, by batch)

FBA inbound shortage rate (units shipped to FBA vs. units receipted, by lot)

Unexplained vendor charge variance (month-over-month delta on 3PL, co-packer, and disposal fees)

Time to complete a lot-level chain-of-custody audit (target: under 10 minutes)

Comparison

What this replaces

The other ways teams handle this today, and how the Starch version compares.

Spreadsheet reconciliation (Google Sheets + manual 3PL/co-packer exports)

Works until you have more than two locations or SKUs — at that point, reconciliation lag means you're always catching shrinkage after the fact, never before.

QuickBooks inventory tracking

Good for accounting entries but has no lot-level traceability, no 3PL receiving reconciliation, and no anomaly detection — you'll know what was written off but not where it actually disappeared.

Cin7 or Fishbowl (mid-market inventory platforms)

More structured inventory management than Starch today, but six-figure implementation costs, no AI-authored custom views, and you're still manually wiring your co-packer and bank transaction data.

Amazon Seller Central FBA reports (manual)

Amazon gives you the data, but you have to pull it yourself, cross-reference it against your own lot records, and build the dispute documentation manually — no automated variance flagging or lot-level matching.

On Starch RECOMMENDED

One platform — transaction insights, lot tracker, inventory planner all running on connected data. Setup in plain English; numbers stay current via scheduled syncs and live agent queries.

Try it on Starch →

FAQ

Frequently asked questions

Does Starch connect directly to my 3PL's system?

It depends on your 3PL. If they have a portal you can log into through a browser, Starch can automate it through your browser — no API needed. If they use a system that's in Starch's integration catalog of 3,000+ apps, the agent can query it live. For 3PLs that send you CSV reports via email, Starch can pull those from your Gmail inbox, which syncs on a schedule.

What about my co-packer? They just send me PDFs and portal logins, no API.

That's the common case, and Starch handles it. If your co-packer has an online portal, Starch automates it through your browser — logs in, pulls production batch data and lot quantities, and feeds it into your reconciliation. If they send PDFs, you can paste or upload the data and Starch extracts and maps the fields. It's not as clean as a direct sync, but it's a lot better than doing it by hand.

Can Starch help me file FBA inbound shortage reimbursement claims?

Starch can identify the shortage by comparing your 3PL outbound records to FBA's receiving confirmations, and it can pull the lot-level documentation you'd need to support a claim. Submitting the claim itself happens through Amazon Seller Central — Starch automates it through your browser if you want to systematize that step.

Lot Tracker and Inventory Planner both say 'currently in development.' When will they be available?

Both are in active development. You can request beta access now and you'll be notified when they launch. In the meantime, you can build a lot-level reconciliation view today using Transaction Insights, connected QuickBooks data queried live from Starch's integration catalog, and browser automation against your co-packer and 3PL portals — it won't have the full FSMA 204-compliant UI, but the underlying data wiring is available now.

Is Starch SOC 2 certified? My retail buyer is asking about data security.

Not yet — Starch is not SOC 2 Type II certified today. If your retail buyer requires SOC 2 certification for any platform touching your operational data, that's an honest constraint to know upfront. It's on the roadmap.

My shrinkage spans both retail (Shopify) and wholesale (UNFI, KeHE). Can Starch handle both?

Yes. Shopify is reachable from Starch's integration catalog — the agent queries it live. For UNFI and KeHE, Starch automates their portals through your browser — no API needed. You can build a single reconciliation view that pulls sell-through data from both channels alongside your 3PL outbound records to see where shrinkage is concentrated.