What it means
An accounting information system has several recognisable components: the source data itself, the hardware and software that process it, the people who operate it, the procedures they follow, and the internal controls that keep it honest. Weakness in any one of them undermines the rest, which is why a business with excellent software and untrained staff still produces unreliable numbers.
The system's job is to turn raw events into information someone can act on. A delivery note, a timesheet and a bank feed all enter as data, get coded and posted, and eventually emerge as a gross margin by product line or a cash forecast for the next quarter.
Modern systems are usually built around a general ledger with connected modules for sales, purchases, payroll, inventory and fixed assets. Larger businesses put these inside an enterprise resource planning platform so that a stock movement in the warehouse updates the ledger automatically, without anyone rekeying anything.
Internal control is baked into the design rather than added afterwards. Segregation of duties, approval limits, automatic three-way matching between purchase order, goods received note and invoice, and an unchangeable audit trail all live inside the system and stop errors and fraud before they reach the accounts.
The commercial argument for investing in one is usually about time and reliability rather than accounting elegance. A system that removes manual rekeying, closes the month faster and gives managers current numbers changes how quickly the business can react, which is worth far more than the licence fee.
In practice
Real-world examples.
Example
A 40 site restaurant group connects its till system directly to the general ledger. Daily sales, card settlements and cash variances post automatically overnight, cutting the monthly close from eleven working days to four and letting area managers see food cost percentages by Tuesday.
Example
A construction firm implements three-way matching in its purchase module. An invoice that does not agree to both the purchase order and the goods received note is held automatically, which stops roughly $60,000 a year of duplicate and overcharged supplier payments.
Example
A fast growing agency outgrows its spreadsheet based system when it opens a second office. Two people are keying the same timesheets into different files, and the move to a single system with role-based access ends the argument about which version of the utilisation report is correct.
Formula
Calculation
There is no standard formula, but the investment case is normally built as an annual net benefit:
Annual net benefit = (hours saved x fully loaded hourly cost) + other costs avoided - annual system cost
Return on investment = annual net benefit / annual system cost
A distribution business currently rekeys supplier invoices by hand. A new system with automated invoice capture is expected to save 40 hours of finance time a month at a fully loaded cost of $35 an hour, and to avoid roughly $4,200 a year of late payment penalties caused by invoices going astray.
Hours saved per year = 40 x 12 = 480 hours.
Value of time saved = 480 x $35 = $16,800.
Total annual benefit = $16,800 + $4,200 = $21,000.
The system costs $800 a month in subscription plus $2,400 a year in support.
Annual system cost = ($800 x 12) + $2,400 = $9,600 + $2,400 = $12,000.
Annual net benefit = $21,000 - $12,000 = $9,000.
Return on investment = $9,000 / $12,000 = 75%.Case study
Seen in the real world.
The following is an illustrative and entirely fictional example. Calder Fresh Foods, an invented chilled goods wholesaler, grew from $6,000,000 to $19,000,000 of revenue in four years while still running its accounting on a basic ledger package plus a large collection of spreadsheets. Month end took fourteen working days, and by the time results appeared they described a trading period that had ended a fortnight earlier.
The finance director costed a replacement at $46,000 to implement and $18,000 a year to run. The benefit case rested on 60 hours a month of rekeying and reconciliation at $32 an hour, worth 60 x 12 x $32 = $23,040 a year, plus about $14,000 a year of credit notes caused by pricing errors, giving $37,040 of annual benefit against $18,000 of annual cost.
What actually persuaded the board was not the $19,040 of net annual benefit but the speed. With daily margin data by customer, the fictional company found that its three largest accounts were being served below cost once delivery was included, and repricing them added far more to profit than the system ever cost.
Watch out
Common mistakes.
- Treating the system as purely a software purchase and skipping the process design, training and controls that make it work.
- Automating a broken process, which simply produces wrong numbers faster and with more apparent authority.
- Giving every user full access because it is easier, which destroys segregation of duties and removes the main defence against internal fraud.
Questions
People also ask.
Is an accounting information system the same as accounting software?
No, the software is one component, alongside the data, the people, the documented procedures and the internal controls that surround it.
How long does implementing one usually take?
Anywhere from a few weeks for a small business on a standard cloud package to well over a year for a group replacing an enterprise platform across multiple sites.
What is the most common point of failure?
Data quality at entry, because coding errors and duplicate records at the front end flow through every report the system produces afterwards.
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