The manual process and its hidden costs
When supplier invoice posting relies entirely on human data entry, the real cost goes well beyond the analyst's time. Every manual step introduces risk, and that risk builds up over the month until it complicates the accounting close and accounts payable reconciliation.
The most common hidden costs we see in AP teams are the following:
- Time: hours spent opening XML and PDF files one by one, copying amounts, taxes and supplier data into SAP Business One.
- Data-entry errors: mistyped amounts, RFC, dates or taxes that later force teams to reopen entries and adjust the accounting distribution.
- Lack of traceability: little clarity on who posted each invoice, when and with what supporting documentation.
- Documents without XML: invoices that arrive only as PDF or with a missing XML, which breaks tax validity and stalls posting.
- Rework: duplicates, corrected entries and reprocessing that consume the team during the close.
What an AP add-on automates in SAP B1
An accounts payable add-on for SAP Business One takes the flow that is manual today and turns it into a rules-driven process. The starting point is the CFDI received: the system reads the document's XML and extracts the key supplier data, line items, taxes and totals, without relying on manual entry.
From that reading, the solution runs a sequence of checks before posting the supplier invoice in SAP B1. These checks are adjusted to the rules defined in discovery and to each company's configuration, so that behavior stays consistent with its AP policies.
Broadly speaking, an AP add-on such as SIGITEC's SIGIPRO handles:
- Reading the XML of the CFDI received to extract supplier, line items, taxes and totals.
- Validation against the SAT and against SAP Business One catalogs, according to the agreed criteria.
- Application of business rules by supplier and expense type defined in discovery.
- Automated assignment of cost centers and accounting distribution.
- Posting of the supplier invoice in SAP B1 with its associated supporting documentation.
Cost centers and accounting distribution
One of the most time-consuming tasks in accounts payable is deciding how each invoice is split across cost centers and accounting accounts. When this is done by hand, it depends on the analyst's judgment and their memory of each supplier, which creates inconsistencies between periods and makes reconciliation harder.
By automating posting, the accounting distribution stops being a repetitive decision and becomes governed by rules. Distribution criteria are configured by expense type and by supplier, so that an invoice for a recurring service or a specific input is always assigned to the same cost centers and accounts, according to the agreed scope and configuration.
These rules are defined during discovery, together with finance and controllership, to reflect the company's real cost structure. The goal is not to replace the team's judgment, but to write it down once and apply it consistently to every CFDI received, while keeping the ability to review and adjust when a case requires it.
What documents you need in order before automating
Automation does not start from scratch: it builds on the master data and policies that already exist in the company. The more orderly these elements are before starting, the cleaner the rollout and the fewer adjustments afterward.
Before automating supplier invoice posting, it is worth having the following in order:
- RFC and SAP catalogs in order: suppliers, accounting accounts and cost centers updated and cleaned up.
- Rules by supplier and expense type: how each type of invoice should be posted and distributed.
- Permissions and authorizations: who can post, review and approve within the accounts payable flow.
- Validation criteria: what is validated against the SAT and the catalogs, and how exceptions are handled.