ACCOUNTING SERVICES / RECORDS
Good accounts payable and receivable processes connect each invoice to an approval, a payment or a collection. They help a business see what is due, prevent duplicate settlements and understand why cash has not arrived even when a sale is recorded.
Our scope discussion can cover customer billing, supplier-bill recording, ageing reports, payment proposals and reconciliation. Agree who communicates with customers and suppliers, who approves changes and who is authorised to release money. Bookkeeping access should not automatically grant payment authority.
Information reviewed 13 November 2026 · Pimaccounting
Customer invoicing and receivables
Start with approved commercial terms: the contracting entity, customer details, delivery or service milestones, currency, credit period and supporting purchase-order requirements. A complete invoice issued to the correct entity is easier to collect than one corrected repeatedly after the due date.
The receivables ledger should show original invoices, credit notes, receipts and remaining balances. Record a customer deposit separately until its accounting treatment has been assessed. When a customer pays several invoices together, obtain a remittance breakdown rather than allocating the amount to the oldest balance without checking.
- Maintain customer details and document changes.
- Check billing against contracts and approved delivery evidence.
- Track due dates, disputes and promised payment dates.
- Match receipts, withholding certificates and bank charges to the correct balance.
- Review old debts and proposed adjustments with management.
A collection reminder process can be included if expressly agreed. Escalation of disputes, legal recovery and decisions to compromise a debt require the appropriate management or legal authority.
Supplier bills and accounts payable
Supplier invoices should be checked against the purchase, delivery and agreed terms before being entered for payment. Use a consistent supplier record with the legal name, tax information, approved contact and independently verified payment details. A request to change bank details deserves separate confirmation through a known contact route.
The payment proposal should identify the supplier, invoice, due date, gross amount, any tax deduction and the proposed net payment. Mark disputed, duplicated or unsupported bills clearly. Approval of an expense and approval of a bank transfer are separate controls and should be assigned accordingly.
Review supplier statements against the ledger. An invoice can be missing from your records even when the bank reconciliation is complete, because it has not yet been paid. Conversely, a payment may have been recorded without clearing the original invoice, leaving a misleading outstanding balance.
Invoices, tax invoices and withholding evidence
A commercial invoice, a VAT tax invoice, a receipt and a withholding certificate serve different purposes. The document title alone does not make it valid. VAT registration status, the tax point, prescribed fields and the nature of the transaction determine the requirements. The Revenue Code sets out the tax-invoice rules; non-authorised businesses must not issue VAT tax invoices as though registered.
For a payment subject to withholding, separate the supplier’s revenue or expense amount from VAT, the tax withheld and the net bank payment. Review classification before payment rather than trying to infer the correct rate from the software default. The withholding tax guide explains the additional checks and the conditional electronic remittance regime.
Illustrative reconciliation
Assume a domestic service invoice has a THB 10,000 fee, THB 700 VAT and a separately confirmed THB 300 withholding obligation. The supplier receives THB 10,400 in cash and a THB 300 withholding credit supported by the appropriate evidence. The THB 10,700 invoice is reconciled using both components. This example assumes the tax treatment has already been confirmed; it does not establish a rate for every service or payment channel.
Ageing reports and working-capital decisions
On smaller screens, scroll the table sideways to see all columns.
| Report | What to examine | Management action |
|---|---|---|
| Receivables ageing | Overdue balances, disputes, unallocated receipts and missing certificates. | Resolve billing issues, agree follow-up and review credit terms. |
| Payables ageing | Due invoices, supplier credits and unpaid disputed items. | Approve a payment schedule and protect critical supply. |
| Cash commitments | Supplier payments alongside payroll, tax, loans and planned purchases. | Identify timing gaps before releasing discretionary payments. |
Define whether ageing is measured from invoice date or due date. A report that mixes both can make customers appear late when their contractual credit period has not ended. Reconcile the totals to the general ledger and retain an explanation for any exclusions.
A practical workflow and handover
- Agree the boundaries. Define invoice creation, document checking, posting, collection follow-up and payment preparation separately.
- Clean the master data. Check duplicate customer and supplier accounts, tax details and opening balances.
- Set approval rules. Assign responsibility for prices, credit notes, refunds, purchases and bank-detail changes.
- Reconcile regularly. Match ledger balances to statements, customer correspondence and actual cash movements.
- Review exceptions. Keep an action list for disputed items, missing documents and unmatched settlements.
Prepare customer and supplier lists, outstanding invoices, payment terms, sample documents and the last reconciled ledger. For businesses using marketplaces or payment processors, include settlement reports showing fees and refunds. Electronic invoicing can improve the exchange, but it must follow the relevant Revenue Department system requirements where statutory e-tax treatment is intended.
Billing and payment questions
Will an accounting provider release our bank payments?
Only under a separately agreed authority and control process. A normal preparation scope can produce a payment proposal while your authorised signatories retain final bank approval.
Why does the customer’s payment differ from the invoice?
It may include withholding, fees, a credit note, a partial payment or a dispute. Obtain the breakdown and supporting evidence before clearing the balance or writing off the difference.
Can an invoice be deleted after it has been issued?
Use the appropriate correction process and preserve the document history. The right treatment depends on the document, transaction and tax period; deleting it from software can remove an essential audit trail.
Is debt collection included?
Routine reminders and customer queries can be discussed as part of a scope. Negotiated settlements, formal disputes and legal recovery are separate decisions and may require specialist assistance.
What is needed for a first review?
Provide an aged receivables and payables report, the trial balance, sample invoices, recent bank statements and a list of disputed or unexplained items. Identify the people authorised to approve adjustments.
Official references and further reading
- Revenue Department — VAT registration and tax invoices, sections 85–86
- Revenue Department — income tax guide for foreign companies
- Revenue Department — e-Tax Invoice & e-Receipt
- Revenue Department — withholding order Tor Por 4/2528, as amended
References checked on 13 November 2026. Current legislation, official notices and the facts of the case take precedence over older summaries. This guide provides general information; confirm the applicable treatment and engagement scope before acting.
Plan the right scope for your business
Tell us about your activity, current records and upcoming deadlines. We can discuss the work, responsibilities and documents needed for a tailored quotation.
Request a consultation