Stock control alongside your accounting software

Accounting software and stock control do different jobs. Accounting software is built around invoices, ledgers and tax: what you sold, what you bought, what you owe and what you are owed. Stock control is built around movements, locations, counts and who changed what: where every unit is right now, and how it got there. Many small businesses run both, and the two work well together when each one owns a clear part of the work and a shared reference ties them together.

This guide explains when a separate stock system helps, how to split responsibilities between the two tools, and how to keep them in step with invoice numbers and a monthly reconciliation. It ends with a checklist and answers to common questions.

Two tools, two jobs

Many accounting, bookkeeping and invoicing tools include stock features, such as item lists, quantities that go down when you invoice, and stock value reports. For a business with one storeroom and one person handling stock, that can be all you need.

The questions each tool is designed to answer are different, though.

When the second column starts to matter day to day, a separate stock system is worth considering.

When a separate stock system helps

• Stock sits in more than one place. A warehouse, a shop, a few vans, a customer site. You need stock per item and per location, and transfers between locations that don't count as sales or purchases.
• Several people change stock. Each person records receipts, issues and corrections. You need to know who did what, and to limit each person to the locations they work in.
• Some changes need a second pair of eyes. A large count correction or a price change should wait for someone else to approve it.
• You count stock regularly. Counts produce corrections. You want each correction recorded as its own entry with a reason, not as a quietly changed number.
• Stock moves without an invoice. Samples, damaged goods, internal use, returns to a supplier awaiting a credit note, and transfers between locations all change stock before, after or without an invoice.
• You need an audit trail for stock. When a number looks wrong, you want to trace it back to the exact movements, with dates, names and references.

If none of these apply, the stock features in your accounting tool may be enough. If several apply, read on.

Split the responsibilities

The simplest rule: accounting owns money, stock control owns units. Decide once which tool is the record for each piece of information, and write it down for the team.

Use the same item codes (SKUs) in both tools. One code, one item, in both places. This is the single most useful thing you can do to make reconciliation easy.

Keep both in step: a worked example

LightInventory does not connect to accounting software today, so there is no automatic sync. The workflow below keeps the two in step by hand, and it works the same way with a stock ledger kept in Google Sheets. See inventory management in Google Sheets for that ledger design.

The shared reference

Every stock movement has a reference. When a movement relates to an invoice, the reference is the invoice number, typed exactly as it appears in the accounting software.

Movements without an invoice get their own reference series (TR- for transfers, DMG- for damage, CNT- for counts), so every movement can be traced and nothing is left blank.

During the month

1. When a purchase invoice is entered, the person receiving the goods records a Receive movement with the invoice number as the reference. If the goods arrive before the invoice, use the supplier's delivery note number as the reference and match it to the invoice at month end.
2. When a sales invoice is issued, the person shipping records an Issue movement with the invoice number.
3. Transfers, damage and counts are recorded in the stock system only.

At month end: reconcile quantities

1. Export stock and movements for the month from the stock system. In LightInventory, permitted roles can export stock and history as CSV, XLSX or PDF. The Stock tab in your Sheet also shows stock per item and location at any time.
2. Match invoices to movements. List the invoice numbers from the accounting software for the month. List the references on Receive and Issue movements. Every invoice that includes stock items should appear in both lists. An invoice with no movement means goods were invoiced but not recorded as shipped or received, or the other way round.
3. Compare quantities per item. If your accounting tool also tracks quantities, compare its closing quantity per SKU with the stock system's total across all locations. Differences should be explained by movements that have no invoice: damage, internal use, count corrections.
4. Record the non-invoice movements in accounting. Add up the Adjust movements for the month (damage, count corrections, internal use) and pass the totals to whoever keeps the books, so stock value on the accounting side reflects them.

At month end: check stock value

1. Take the closing quantity per item from the stock export and multiply it by the item's cost. Your Items tab holds a cost for each item.
2. Compare the total with the stock value in the accounting software.
3. Expect small differences if the two use different costing. Accounting software may value stock with a method such as average cost, while a simple quantity times cost uses one cost per item. Quantities should match exactly; values should be close, and any gap should be explainable.
4. Keep the export and a short note of what you found with the month's records.

Done every month, this takes little time, because differences are small and recent. Done once a year, it can take days.

How LightInventory fits

LightInventory is an inventory app built on top of a Google Sheet you own. It handles the stock control side of the split above.

• Movements, not overwritten numbers. Every receipt, issue, transfer and adjustment is a row in a Movements tab, with quantity, reference, note and who made it. Stock on hand is calculated from those rows, per item and location.
• A history with the reason. Every change is recorded in a Log tab with who, what, when and why, including the movement's reference. The history is tamper-evident: a quietly edited or deleted entry fails verification. See the audit trail.
• Approvals you choose. You decide which changes wait for review, for example stock adjustments or price and cost edits. Nobody can approve their own request.
• Roles and locations. Owner, Admin, Approver, Editor and Viewer, with Editors and Viewers limited to the locations you choose.
• Fixes without erasing. A mistake is corrected with a revert, which adds a new entry that cancels the old one, so the month-end figures and the history agree.
• Your data stays in your Sheet. If you stop using LightInventory, you keep the file.

There is no integration with accounting software today. The invoice number on each movement and the month-end export are the link between the two. Plans are on pricing.

Checklist

1. Write down which tool is the record for money and which for units.
2. Use the same SKU for each item in both tools.
3. Put the invoice number on every movement that relates to an invoice.
4. Give non-invoice movements their own reference series.
5. Decide, with your accountant, whether the accounting tool also tracks quantities.
6. Choose which stock changes need approval.
7. Count stock on a schedule and record each correction with a reason.
8. Reconcile invoices, quantities and value every month, and keep the export.

Questions

Does LightInventory sync with my accounting software?

No. There is no integration with accounting software today. You keep the two in step by putting the invoice number on each related stock movement and reconciling at month end with an export from LightInventory.

Should stock quantities live in both tools?

It depends on how your books are kept. Some businesses keep quantities in both and compare them every month; others keep quantities only in the stock system and record stock value in accounting at month end. Ask your accountant which suits your business, and write the decision down.

What if goods arrive before the invoice?

Record the Receive movement when the goods arrive, using the supplier's delivery note number as the reference. When the invoice comes in, list the delivery note number next to the invoice number on your month-end reconciliation, so the match can still be made.