The open items list: the foundation of cash forecasting

The open items list is one of the most useful reports in accounting: it shows every invoice that has been posted but not yet paid at a given date. On one side, the outstanding receivables from your customers; on the other, the outstanding payables to your suppliers.

For collections it has always been essential. Its real value for financial control lies elsewhere, though: the open items list is the central data source for any short-term cash forecast — because every open receivable is an expected receipt, and every open payable an expected payment.

What is an open items list?

An open items list is the schedule of all invoices not yet settled at the reporting date. Every item appears with amount, due date and counterparty — and drops off automatically as soon as it is paid. The list therefore never shows total revenue, only what is still outstanding.

They are called open items because the receivable or payable exists in the books while the payment process is not yet complete. In the general ledger, open items arise continuously: a sales invoice is posted and is an open receivable item from that moment until the customer pays; a purchase invoice is an open payable item until you settle it. Only the receipt or payment clears the item — in accounting terms, invoice and payment are matched to each other.

This makes the open items list fundamentally different from a revenue or invoice report. It is a snapshot of what is still outstanding on a particular date. Pull the same list a week later and it looks different: settled items have gone, new invoices have appeared. That currency is exactly what makes it so valuable for short-term control — it does not show what was once invoiced, but what is still owed today.

Receivable and payable open items

The list has two sides that need to be kept apart. The accounts receivable side holds outstanding receivables — money your customers still owe you. The accounts payable side holds outstanding payables — money you still owe your suppliers. Together they give the picture that matters for liquidity: what comes in, what goes out.

The amounts in the table are illustrative only. What matters is the principle: the difference between open receivables and open payables tells you nothing about liquidity on its own, because it carries no timing. A receivable due in two weeks affects the bank balance quite differently from one due in ten.

In practice accounting keeps the two sides separate because they serve different processes: the receivable side drives credit control and the dunning run, the payable side drives payment scheduling and early-settlement-discount decisions. For the liquidity view they are brought back together — one side becoming the money coming in, the other the money going out.

What the open items list is for

The list does three jobs in practice. First, visibility of what is outstanding: at a glance you see how much money sits with customers and which invoices are overdue. Second, collections: the receivable side is the working basis of every dunning run — overdue items are identified and chased before they turn into write-offs.

The third job is the most important and the most often overlooked: the open items list is the base of the cash forecast. Every open receivable item is an expected receipt, every open payable item an expected payment. Sort the items by when payment is likely and you have the skeleton of the coming cash flows — without having to estimate a single value. The numbers are already in the books; they only need distributing correctly.

For the list to do these jobs it has to be current and exportable. Every general ledger system can produce one as a standard report: in DATEV under the accounts receivable and payable analyses, in SAP Business One via the business partner reports, and under an equivalent name in every other package. In each case it is a routine export, not an integration project — the list already exists in your accounting system and simply needs pulling regularly.

A few fields matter particularly for planning: the counterparty, the open amount, the invoice date and due date, and — where recorded — the agreed payment terms. Between them these let you place each item in the week payment is expected. The more complete the export, the less has to be filled in by hand afterwards. If you already pull the list weekly for collections, you are holding the planning data set already.

How the list feeds the 13-week forecast

The route from open items to forecast is short. Each open item is assigned to the week in which payment is expected — for receivables from the payment terms and the customer’s actual behaviour, for payables from the due date. The weekly totals become the lines of the 13-week cash forecast: receivable items sum to receipts, payable items to payments.

Opening balance plus expected receipts less expected payments gives each week’s closing balance — and across 13 weeks, the curve on which you read the low point of your liquidity. Because the list supplies the real outstanding amounts, that forecast rests on actual figures rather than estimates. The manual effort sits entirely in distributing the items across the weeks each time — and that step repeats at every update.

Not every item is actually paid on its due date, and this is where a forecast built naively from due dates goes wrong. Customers who habitually pay late belong in a later week than the nominal terms suggest; reliable payers belong in the week of the due date. These judgements get refreshed at every roll-forward, because the current list shows which items have cleared since last week and which have stayed overdue. The plan gets more realistic with every update — provided the open items list is the basis and not a detached estimate. Keeping the receivable side from silting up with overdue items is the job of DSO discipline, and the two reinforce each other: a cleaner list makes a better forecast.

This is where LiquidityLens comes in. It plans directly from your open items lists and exports from SAP Business One or DATEV. You upload the list you already pull, and LiquidityLens assigns the open items to weeks and builds the 13-week outlook. No interface project, no connection to the general ledger, no IT effort: the open items list is the data source and the export is enough. At the next roll-forward you upload the updated list and the outlook moves on a week — the recurring assignment step disappears.

Frequently asked questions