How one till handles riel and dollars in the same sale
Cambodian shops price in dollars and give change in riel. Here is why, and what it demands of the software behind the counter.
- Cambodian tills price in USD and give change in KHR because the National Bank pulled $1, $2 and $5 notes out of circulation from mid-2020.
- The 4,000:1 rate at the counter is a market convention, not a legal peg. The 2025 average was 4,011.
- The riel passed the dollar inside Bakong in 2025 at 58.2% of transaction volume, up from 49.3%.
- A till that treats one currency as the exception will drift, because rounding applied at the wrong layer breaks the drawer count.
Why does a Cambodian shop price in dollars and give change in riel?
Because there are no small dollar notes left to hand back. In May and June 2020 the National Bank of Cambodia moved to take USD 1, USD 2 and USD 5 notes out of circulation: banks and microfinance institutions had from 1 June to 31 August 2020 to collect them and ship them out, with the central bank covering the freight inside that window. That was reported at the time by VOA Khmer and The Diplomat as an instruction to the banking sector, not as a statute banning the notes. The effect on the counter was immediate. Once small dollars stopped coming back through the banks, they stopped coming back over the counter.
So the arithmetic runs in two directions all day. A customer buys a $4.50 item and hands over a $10 note. The change is $5.50, there is no $5 note to build it from, and the drawer returns 22,000 riel. Run the same sale the other way and it arrives as a 20,000-riel note against a $4.50 price, and the till owes 2,000 riel back. Neither is an edge case. Together they are most of the shift.
The dollar is the unit of account; the riel is the unit of change. Software that treats one as the real currency and the other as a conversion bolted on at the end will be right most of the time, and wrong on exactly the sales that cost money: the mixed tender, the partial refund, the shift that closes short.
Is the 4,000 rate a law?
No. No statute or Prakas fixing the riel to the dollar at 4,000 appears in the published record. It is a market convention, kept because it divides cleanly in the head and on a price list. The National Bank's own published average was 4,011 riel to the dollar in 2025, and 4,071 in 2024. The counter rate is a rounding of a rate that moves, not a peg that holds the rate still.
The gap between 4,000 and the published average is small, and which side of the counter it falls on depends on which way the money is moving. Riel taken as tender is credited slightly high: a 4,000-riel note buys a full dollar of goods when the average says it is worth a shade less. Riel handed back as change is slightly short, by the same logic. Across one sale that is nothing. Across a year of sales it is a figure, and you can only measure it if the software applied the rate the same way every time.
So the real decision is not which rate to use. It is where the rate lives. A rate held in one place, applied once per sale and stored with that sale, can be changed on a Monday morning without rewriting the previous week's history. A rate typed separately into a receipt template, a report and a refund screen will disagree with itself the first time somebody updates one of the three.
Is Cambodia moving off the dollar?
Two things are true at once, and a shop has to plan for both. Inside Bakong, the national payment system, the riel passed the dollar in 2025: 58.2% of transaction volume, up from 49.3% a year earlier and 18.2% in 2020. In the banking system, dollarisation has barely shifted. 90.7% of deposits were still held in foreign currency in 2025. Digital payments are moving to riel far faster than balance sheets are.
| Year | KHR share | USD share |
|---|---|---|
| 2020 | 18.2% | 81.8% |
| 2021 | 20.1% | 79.9% |
| 2022 | 21.5% | 78.5% |
| 2023 | 34.2% | 65.8% |
| 2024 | 49.3% | 50.7% |
| 2025 | 58.2% | 41.8% |
Cash is not receding either. The same Financial Stability Review puts the growth in currency held outside the banking system at 22.4% in 2025, which is not what a cashless story predicts. The counter still has to serve the customer scanning a QR code and the one behind them paying with a folded 10,000-riel note, into the same drawer count. Nothing in the trend line lets you drop a currency.
What does that actually demand of the software?
One rate per sale, stored with the sale, and one rounding rule applied at one layer. Nearly every dual-currency defect on a real till traces back to a rate or a rounding decision made in more than one place. Four of them show up again and again.
- Rounding per line versus per sale. Round every line to the nearest riel and the total drifts from the figure a customer can add up on their phone. Round once, at the total, and the printed lines still have to sum to it.
- A refund at the wrong rate. A sale rung at one rate and refunded at another leaves a difference with nowhere to post it. A refund has to reverse the sale, not re-price it at today's number.
- Tax computed in one currency and reported in the other. Compute VAT on a converted total rather than on the amount actually charged and the report disagrees with the receipt by a rounding, in the same direction every time.
- One drawer figure instead of two. A shift that reconciles a single converted total hides a shortfall in one currency behind a surplus in the other. Two counts, two expected figures, two variances.
Scale POS holds USD and KHR throughout in integer minor units, with one rounding rule applied the same way across sale, refund, tax and report: one rule, one layer, no per-screen variation. Shift close declares a float and compares expected against counted per currency, so a drawer long in riel and short in dollars reads as two variances rather than one aggregate figure that looks fine. What else a till has to survive here, from KHQR to a dropped connection, is on the POS systems page.
What should you check before you buy?
Ask for a demo till and run five transactions on it yourself. Each takes under a minute, and each exposes a decision the vendor made months ago that you will not be able to change later. Watch the screen and the printed receipt, not the slide deck.
- Ring a $4.50 item, tender 20,000 riel, and read the change on screen and on the printed receipt. Both should say 2,000 riel, and both should show what was handed over.
- Ring a two-line sale, pay part in dollars and part in riel, then refund one line. The refund should come back at the rate the sale used, down the tender it arrived on.
- Close a shift with cash in both currencies. The report should show an expected and a counted figure for each one, not a single converted total.
- Print a receipt and look for both currencies on it: the price, the tender and the change, each in the currency it was actually in.
- Change the exchange rate in the back office, then reopen yesterday's sale. Yesterday's numbers should not have moved.
Frequently asked questions
- Do I have to price in riel?
- Most shops price in dollars and settle the remainder in riel, and a dual-currency till does not force that choice either way. What matters at the counter is that the software can take payment in either currency and hold both on the same sale, whichever one the price list is written in. If the question behind it is a tax one rather than a counter one, ask your accountant, not a POS vendor.
- What rate should I use at the counter?
- 4,000 riel to the dollar is the working convention, and it sits close enough to the published average (4,011 in 2025, 4,071 in 2024) that most shops never revisit it. The number matters less than the discipline around it: one rate for the whole sale, stored with that sale, so a refund next month reverses what was actually charged rather than re-pricing it at that day's rate.
- Can I keep a fixed rate in the system instead of updating it?
- Yes, and most shops do. A fixed counter rate is a business decision, not a software limitation. The requirement on the software is narrower: changing that rate is one edit in one place, and it applies from that moment forward rather than reaching backwards into sales already closed.
- How do I close a drawer that holds both currencies?
- Count each currency separately and compare each against its own expected figure. A single converted total can look correct while hiding a dollar shortfall behind a riel surplus. That is the version you find months later and cannot trace. Two counts, two variances, and a reason recorded against each. If a vendor's shift report can only produce one combined figure, you have your answer about whether it was built for a Cambodian counter.
Where to go next
What a POS system costs and covers in Cambodia sets out the till, the hardware and the support around it. What happens when the connection drops covers the other thing a Cambodian counter quietly gets wrong. Ten POS systems compared records which vendors state that they hold two currencies on one sale and which say nothing at all. The Scale POS product page shows the register and the owner's dashboard as they actually run.