OCR Invoice Processing Cuts Time by 70%: One Power App, Three Processes for a 350-Employee Municipal Government

A case study on replacing three separate paper and email-based accounts payable processes, vendor invoices, employee expenses, and Visa card expenses, with vendor invoice automation built around OCR invoice processing, a Power Apps approval workflow, and a Power BI accounts payable dashboard giving finance leadership visibility into every dollar in the queue. 

Executive Summary

A mid-size municipal government with roughly 350 employees and a community of approximately 50,000 residents was running vendor invoices, employee expenses, and Visa card expenses through three separate, largely manual processes built around paper forms, shared inboxes, and spreadsheet tracking. Code Creators designed and delivered a SharePoint home site alongside a unified Accounts Payable Power App, an OCR invoice processing flow built in Power Automate, a Power Apps approval workflow that routes through AP staff, department managers, and the Mayor’s office, and a Power BI accounts payable dashboard for finance leadership. Average invoice processing time dropped from roughly 10 business days to about 3, a 70% reduction, while manual data entry per invoice fell from about 12 minutes to roughly 3 thanks to AI Builder extraction, a 75% reduction. The project ran 16 weeks from discovery through go-live and included a full training program for AP staff, managers, and administrators.

About the Client 

The client is a mid-size municipal government serving a community of approximately 50,000 residents, with a municipal workforce of roughly 350 employees spread across finance, public works, administration, and other core departments. Like many local governments, day to day financial operations run through a mix of legacy systems and manual processes that were never designed to scale with the volume of vendor invoices, employee expense claims, and corporate Visa card transactions the organization now processes each month. 

Municipal finance carries a layer of accountability that most private sector accounts payable teams do not: payment batches ultimately require Mayor or Deputy Mayor review before processing, budget tracking has to tie back to publicly reported capital and operating budgets, and document retention has to meet municipal audit and legislative requirements set by statute. Any automation effort had to work within that governance structure from the start. 

The Problem 

Before this project, the client’s accounts payable process ran as three effectively separate workflows: vendor invoices arrived by mail or email and were manually keyed into the finance system, employee expense claims were submitted on paper forms routed for physical signatures, and monthly Visa card statements were reconciled line by line against paper receipts. None of the three shared a common intake point, a common approval structure, or a common source of truth for status. 

That fragmentation had a real cost in both time and risk. A typical invoice took roughly 10 business days to move from receipt to payment, largely because each approval step, AP review, department manager sign off, and final AP sign off, depended on a person physically finding and forwarding a paper file or email thread. Manual data entry for a single invoice, keying vendor name, amount, GL code, and purchase order number by hand, took an estimated 12 minutes per invoice, and that time scaled linearly with volume, with no efficiency gain as volume grew. Budget visibility was similarly manual: a manager approving an invoice had no automatic view of year-to-date spend against the relevant GL code, which meant over budget situations were sometimes caught only after approval, when it was already too late to act on them. 

Records management added another layer of risk. Municipal retention requirements differ by expense type, capital invoices need to be retained for the life of the associated asset while operating expenses follow a defined retention period and enforcing that distinction manually across paper and shared drive files left real exposure at audit time. 

What We Discovered 

Before building anything, Code Creators mapped the client’s three accounts payable processes end to end, from the moment a vendor invoice or expense claim entered the organization to the moment it was archived after payment. 

Process and Approval Mapping for Vendor Invoice Automation 

We documented the full approval chain for vendor invoices, employee expenses, and Visa card expenses separately, since each followed a different path. Vendor invoices needed department-level GL coding and manager sign off with budget checks; employee expenses needed manager approval only; Visa card expenses needed cardholder self-service reconciliation before manager approval. This is what confirmed a single unified form could still serve all three, provided the form adapted its fields dynamically to the request type. 

Governance and Approval Routing Requirements 

Because payment batches ultimately need Mayor or Deputy Mayor sign off, and because certain departments route invoices through an admin coder before manager approval while others do not, we worked with finance leadership to document the exact routing logic: which departments have an admin coder step, how manager assignment is determined by department and dollar amount, and what dollar threshold triggers a secondary approver automatically. 

Document Retention Requirements 

We reviewed the client’s municipal retention obligations in detail: capital invoices retained for the life of the associated asset, operating expenses retained for a defined period such as seven years, with disposition handled automatically based on document metadata. This shaped the SharePoint document library structure from the very start of the project. 

The OCR Invoice Processing and Approval Workflow Solution 

The objective was a single accounts payable experience that could handle three different request types without asking users to learn three different systems, while giving finance leadership and the Mayor’s office the visibility and audit trail a public sector organization needs. 

We built a SharePoint home site as the organization’s hub, with a dynamic menu bar, a responsive banner, a targeted quick links section, a news and announcements feed, and a document library with permission-controlled access, giving every employee one place to reach organizational resources. On top of that, we developed a unified Accounts Payable Power App with a Request Type dropdown that dynamically surfaces the correct fields for Vendor Invoice, Employee Expense, or Visa Card Expense submissions. Employees use this dropdown directly when submitting an expense claim or reconciling a Visa transaction, while vendor invoices reach the same form through an automated intake path, since vendors are external parties who never log into the client’s systems. 

Each of the three request types enters the system differently. Vendor invoices arrive by email at a central AP inbox. A Power Automate flow watches that inbox, identifies vendor invoice submissions, stores the attachment in the appropriate SharePoint library, creates a tracking record, and calls the AI Builder invoice processing model, a prebuilt Power Automate action trained specifically to read invoice documents, to extract the vendor name, invoice number, total amount, and purchase order number directly from the attached file. That extracted data pre-populates the AP Power App form, so the AP Clerk opens an already mostly completed vendor invoice record and simply reviews it.  

Employee expense claims skip email intake entirely: an employee opens the AP Power App directly, selects Employee Expense from the Request Type dropdown, and enters the claim by hand, since there is no external document for AI Builder to read. Visa card expenses follow a third path: an AP administrator uploads the monthly card statement once, a Power Automate flow parses it into individual transactions automatically, and each transaction routes to the correct cardholder, who logs into the AP Power App to reconcile their own transactions, adding a business purpose and GL code, before manager approval. 

For vendor invoices, the Power Apps approval workflow routes the request through AP Admin review, department manager approval with automatic budget checks against year-to-date spend, and final AP team sign off, with a secondary approver triggered automatically for invoices above a defined dollar threshold and a warning surfaced if year-to-date spend crosses 90% of the allocated budget. Employee expense claims follow a lighter path straight to manager approval, without the admin coder or secondary approver steps, matching how the organization handled expense sign off before automation. Once manager approved, an expense claim joins the same payment batch as approved vendor invoices, since both ultimately require an outgoing payment. Visa card transactions work differently: once a cardholder reconciles a transaction and a manager approves it, the record posts directly to Great Plains for expense recognition, since the purchase was already paid through the card and needs no further payment run. 

Once vendor invoice and employee expense approvals are complete, the Mayor or a delegated Deputy Mayor reviews the consolidated payment batch, covering both vendor invoices and expense reimbursements, in a read-only view and provides final sign off before it exports to CSV for upload into the client’s Great Plains ERP and payment is released. After payment, the batch archives automatically. A Power BI accounts payable dashboard rounds out the solution with 8 KPIs covering total, approved, rejected, and pending invoices and expenses, 6 interactive charts covering budget status, approval trends, and department-level spending, and 2 filterable lists giving finance staff an automatically refreshed, queryable view of everything moving through the system. 

Challenges Overcome 

Making One Form Serve Three Different Request Types Cleanly  

Vendor invoices, employee expenses, and Visa card expenses each needed different fields, different validation rules, and different approval paths, and a form that tried to show all of them at once would have been unusable. Code Creators solved this by building the Request Type dropdown as the true branching point of the form, dynamically rendering only the fields relevant to the selected type at each stage, so an employee submitting an expense claim never sees GL code and purchase order fields meant for vendor invoices, and an AP Clerk reviewing a vendor invoice never sees Visa reconciliation fields meant for cardholders. 

Automating Approval Routing That Depends On Department And Dollar Amount  

Not every department routes invoices through an admin coder, and manager assignment depends on a combination of department and dollar amount. Code Creators addressed this by building the routing logic against a SharePoint list of department, admin coder, and approver hierarchy data supplied by the client, so routing decisions come from configurable data a business user can update directly, without needing a developer every time a department’s approval chain changed. 

Getting AI Builder’s Invoice Extraction Accurate Enough to Trust for Pre Population  

Invoice formats vary by vendor, and an extraction model that only worked reliably on a handful of common templates would have created more correction work than it saved. Code Creators addressed this by testing the AI Builder invoice processing model against a representative sample of the client’s actual vendor invoices during the build phase, tuning which fields it attempted to auto populate, invoice number, vendor name, total amount, and purchase order number, versus leaving for manual entry, so AP Clerks could trust the prepopulated fields without having to double-check every field. 

Results & Business Impact 

The client now runs all three accounts payable request types through one Power App, with invoices moving from receipt to payment in roughly 3 business days, down from 10, a 70% reduction driven by vendor invoice automation and automated routing that replaced manual handoffs. OCR invoice processing cut manual data entry per invoice from an estimated 12 minutes to about 3, a 75% reduction that compounds across hundreds of invoices a month. 

Budget visibility improved directly at the point of approval: managers now see year-to-date spend and remaining budget automatically when entering a GL code, with an automatic warning at 90% of budget utilization, catching potential over budget situations at the moment of approval. Document retention is now enforced by metadata-driven rules, with capital invoices and operating expenses following their respective retention schedules automatically. The Mayor’s office reviews payment batches through a single consolidated, read-only view before payment is released, and finance leadership has continuous visibility into invoice and expense status through the Power BI accounts payable dashboard, with no need to wait on manually compiled reports. 

The day to day impact varied by role. AP Clerks open a mostly completed vendor invoice record pulled in through AI Builder, turning what used to be data entry into a quick review. Department managers see year to date budget status the moment they open an invoice for approval, catching a potential overspend at the point of approval, before it happens. The Mayor’s office reviews one consolidated, read-only payment batch before release, giving elected officials real oversight without requiring a signature on every single item. Finance leadership pulls up the Power BI accounts payable dashboard to see exactly what is pending, approved, or flagged across the whole organization, with no need to wait on a manually compiled status report. 

Lessons Learned 

A few things from this project are worth carrying into any public sector Power Platform implementation: 

1. Government approval chains are rarely a straight line, and the system should reflect that department specific admin coder steps, dollar amount-based manager assignment, and secondary approver thresholds are not edge cases in municipal finance, they are the normal shape of the process, and building routing logic against configurable data is what makes the system maintainable as those rules change. 
2. OCR speeds up the work, it doesn’t replace the review. Pre-populating fields from a scanned invoice through the AI Builder invoice processing model saves real time, but the AP Clerk review step stayed in the workflow deliberately, since accounts payable in a public sector context has to be defensible at audit time above all else. 
3. Retention policy belongs in the data model from day one. Municipal retention rules are legally driven and vary by expense type, and trying to bolt that logic onto a document library after launch is far harder than designing metadata-driven retention into the SharePoint structure from the start.

Client Testimonial 

“Before this, an invoice could sit at someone’s desk for a week before anyone even keyed it in. Now it comes in, gets read automatically, and is in front of the right approver the same day. The budget warnings alone have saved us from a few uncomfortable conversations after the fact. Our Council and the Mayor’s office also appreciate having one clean view of a payment batch, where it used to be a stack of paper.” 

Director of Finance and Administration