Amazon Marketplace Reconciliation Using OMS

Amazon marketplace reconciliation using OMS helps finance teams compare internal order records with Amazon-side reports, identify settlement differences, and keep transaction data aligned across systems. For sellers managing high-volume order flow, this process often involves matching OMS data, marketplace sales records, settlement files, return activity, reimbursement details, and bank receipts in one repeatable workflow.

Cointab provides a structured reconciliation engine for this process. Finance teams can upload files, map key fields once, run reconciliation, review exceptions, and download audit-ready reports. The same setup can be reused for future periods, which reduces repeated spreadsheet work and makes month-end review more consistent.

Why Amazon marketplace reconciliation matters

Amazon sellers usually track the same transaction through multiple records:

• Internal OMS or order data
• Amazon marketplace sales or order reports
• Settlement or disbursement data
• Return and refund activity
• Bank statement entries
• Supporting master files such as SKU or product mapping data

Even when the business is running normally, these records do not always line up perfectly. Orders can be delayed, refunded, partially settled, charged a fee, or excluded from a period. If teams rely on manual Excel checks, it becomes difficult to isolate the real exception versus a normal timing difference.

A structured reconciliation workflow helps teams:

• Spot missing orders and missing settlements
• Review underpayments, overpayments, and partial matches
• Track deductions, refunds, returns, and reimbursements
• Separate valid open items from data issues
• Keep reports ready for internal review and audit support

How OMS fits into the reconciliation workflow

In this use case, the OMS is usually the business's internal source of truth for orders. That makes it a natural Side A dataset.

Side A: Your internal OMS records

Side A can include:

• OMS order exports
• Sales or order summary reports
• Internal invoice or ledger data
• SKU or item mapping files
• Supporting reports used for lookups or enrichment

Side B: Amazon marketplace records

Side B can include:

• Amazon order or sales data
• Settlement or disbursement reports
• Refund or return files
• Reimbursement data
• Bank receipts where needed for final confirmation

Cointab is designed to compare these two sides in a controlled workflow. Users map the date, amount, and reference fields, then define how the records should be matched.

Typical reconciliation flow

A standard Amazon marketplace reconciliation workflow in Cointab follows a simple sequence:

1. Upload OMS data on Side A.
2. Upload Amazon marketplace reports and related files on Side B.
3. Map the required fields such as order date, amount, and order or transaction identifiers.
4. Add supporting data if needed for lookup or enrichment.
5. Create derived columns where the report needs cleanup or normalization.
6. Run reconciliation manually or on a schedule.
7. Review fully matched, partially matched, unmatched, and skipped records.
8. Download the Excel report for finance review and follow-up.

If a file is missed, it can be added later under the same reconciliation and the report can be refreshed.

What Cointab can match in Amazon reconciliation

Amazon marketplace data often needs more than a simple one-to-one comparison. Cointab supports structured matching logic that can handle several common finance scenarios:

• One-to-one matches
• One-to-many and many-to-one matches
• Net-to-net comparisons
• Partial matches
• Contra-style matching
• Cross-field identifier matching

This is useful when an order appears across different reports in different forms. For example, an OMS order may map to a settlement line after fees, returns, or grouped payout adjustments are considered.

What finance teams review in the report

Once reconciliation is complete, the report dashboard helps teams review each outcome clearly.

Fully matched records

These are records where the identifiers and amounts align according to the configured logic. They confirm that the transaction flowed through the expected systems.

Partially matched records

These are records where the transaction is related, but the amount does not fully agree. In Amazon reconciliation, this may reflect fees, deductions, returns, timing differences, or a settlement adjustment that needs review.

Unmatched records

These are records present on one side but not found on the other. Common examples include:

• An OMS order that has not appeared in the Amazon file
• A settlement item that does not tie back to the OMS data
• A bank entry that cannot be linked to the expected Amazon payout

Skipped records

Skipped records are rows excluded from the reconciliation because of missing data, invalid amounts, duplicates, or another file issue. Visibility into skipped items helps finance teams understand what was not evaluated and why.

Supporting files that improve Amazon reconciliation

For marketplace reconciliation, supporting data is often just as important as the primary reports. Cointab allows optional supporting files that can help enrich, join, or normalize the data before matching.

Common examples include:

• SKU master files
• Product mapping sheets
• Fee or rate files
• Customer or store mapping data
• Return or refund reference files
• Lookup tables used for clean reference fields

These files are not reconciled directly. They help prepare the primary data so the matching logic can work with cleaner inputs.

Derived columns for cleaner matching

Amazon reconciliation data often needs a small amount of preparation before matching. Cointab lets teams create derived columns using AI-assisted formula generation or standard calculated logic.

Examples include:

• Clean order ID
• Normalized transaction reference
• Net amount after fees
• Refund amount as a negative value
• Combined reference field
• Amount excluding tax

This reduces manual spreadsheet work and makes the reconciliation setup easier to reuse across periods.

AI support for open items

After structured matching is complete, AI can help analyze open transactions that are still unresolved. This is useful when references are inconsistent, partner data is incomplete, or the reason for the difference is not obvious from the raw file.

AI can help finance teams review:

• Why a transaction may be unmatched
• Whether a missing file could explain the gap
• Whether a refund, return, fee, or deduction is likely involved
• What action may be needed next

If evidence is not strong enough, the item remains open rather than being forced into a weak match.

Reusable reconciliation for recurring Amazon periods

Amazon marketplace reconciliation is usually a recurring finance process. Teams may need to run it monthly, weekly, or for custom settlement periods.

Cointab is built so the reconciliation can be configured once and reused later. For future runs, teams only need to select the reconciliation, choose the period, upload the files, and run the workflow again. The setup remains available in the dashboard for future reference.

This is especially helpful when:

• The same Amazon process is repeated every month
• The company manages multiple marketplaces or PSPs
• Finance teams need consistent reporting across periods
• Operational teams want a shared workspace with audit history

Automation for recurring marketplace operations

Once the reconciliation is set up, Cointab can support recurring workflows through email, SFTP, or API-based data flow. That makes the process suitable for finance teams that want to reduce manual uploads and keep their reconciliation routine consistent.

Automation can help teams:

• Receive reports on a schedule
• Validate file formats before running reconciliation
• Trigger reconciliation after all required files arrive
• Deliver output back to internal systems when needed

This turns Amazon reconciliation from a one-time spreadsheet task into a repeatable finance operation.

FAQ

What is Amazon marketplace reconciliation using OMS?

It is the process of comparing internal OMS order data with Amazon marketplace reports, settlements, and related records to identify matched, partially matched, unmatched, and skipped transactions.

Which reports are typically used in this workflow?

Teams usually compare OMS exports with Amazon sales or order data, settlement or disbursement files, return or refund reports, reimbursement data, and bank statement entries when needed.

Can Cointab handle partial matches and exceptions?

Yes. Cointab separates fully matched, partially matched, unmatched, and skipped records so finance teams can focus on the exceptions that need review.

Can the same setup be reused for the next period?

Yes. Once the reconciliation is configured, it can be reused for future periods without rebuilding the workflow from scratch.

Can supporting files be added to improve matching?

Yes. Supporting files such as SKU masters, mapping sheets, or fee files can be used to enrich or prepare the data before reconciliation.