How to track client payments: spreadsheet or app?

Why keeping it in your head stops working

With a handful of clients, remembering who paid feels easy. The trouble shows up over time, almost always for the same reasons:

• Cancellations and reschedules. Tuesday's session moved to Thursday. Next week's was canceled. Which one did the client pay for?
• Different payment arrangements. One client pays per session, another pays for the whole month on the 1st, a third paid for a package of five sessions up front.
• Rate changes. Your fee went up in March. Are the February sessions that are still unpaid billed at the old rate or the new one?
• Holidays and time off. In a month with a holiday, a client on a monthly fee has one session fewer. Does the amount change?

Each of these is small. Together, they turn into that end-of-month feeling that the numbers don't add up, without knowing exactly where the gap is.

Before you track anything: the agreement with the client

No tool fixes a vague agreement. Before the first session, put it in writing (in your intake paperwork or in a message the client replies to):

• Your fee and how it's charged: per session, a flat monthly fee, or the sum of the month's sessions.
• When payment is due: before the session, right after it, or on a set day of the month.
• How to pay: card, check, bank transfer, Zelle, Venmo.
• Late cancellations and no-shows: how much notice the client needs to give to avoid the fee.
• Rate increases: when they happen and how much notice you give.

That agreement is what you'll be recording. If it changes, note the date it changed.

What to record for every session

Whatever tool you use, each session needs:

1. The client.
2. The date and time.
3. The fee on that date (the rate that applied then, not today's).
4. What happened: attended, no-show, canceled or rescheduled.
5. Whether it was paid and, if so, on what date.

With that, the rest is arithmetic: how much came in this month, what's still outstanding and from whom.

Option 1: a spreadsheet

A spreadsheet works well if you see a few clients and like to control every detail. A simple layout, in Google Sheets or Excel:

Two formulas cover most of it. To see how much one client has outstanding (attended sessions with no payment date):

=SUMIFS(C:C, B:B, "Client C", D:D, "Attended", E:E, "")

If you charge for no-shows, run the same formula with "No-show" instead of "Attended" and add the two.

To see what came in during a month, add up the "Fee" column for the rows where "Paid on" falls in that month.

Where a spreadsheet starts to strain:

• Your calendar lives somewhere else, so every session gets typed twice.
• No-shows, reschedules and holidays are manual fixes, one at a time.
• Monthly-fee clients don't fit neatly into one row per session: the month is paid at once, but the sessions happen separately.
• A typo in one fee changes the total without anyone noticing.
• Your clients' information sits in a file that goes wherever the spreadsheet goes (email, cloud drives, other computers).

If you spend more than half an hour a week updating the spreadsheet, or you've found a forgotten session months later, it's time to look at an app.

Option 2: a scheduling and payments app

An app built for session-based work ties the calendar to the money: each session sits on your schedule and, once it happens, already knows whether it was paid. When you compare apps, check for:

• A schedule that fills itself in from each client's regular time, without entering sessions one by one.
• Per-session and monthly billing side by side, each client on their own arrangement.
• The fee for each date: a rate increase applies from then on, and older unpaid sessions keep the old rate.
• No-shows and reschedules in one tap, without redoing the math.
• An outstanding total per client, always up to date.
• Where your data lives. In health care this matters. Prefer an app that keeps data on your device, or one that is clear about where it's stored.

Session Flow was built for this. You add a client once, with their time and fee, and the month's sessions appear on your schedule. One tap on "Mark as paid" records the payment, and the app adds up what's outstanding, client by client. Without the cloud, everything stays on your phone. The app is not a clinical record: it keeps only what the schedule and the payments need. It's free for up to 4 clients.

The ten-minute weekly routine

Spreadsheet or app, tracking only works with a regular check. Pick a day of the week and always go in the same order:

1. Review the week's sessions. Did they all happen? Record no-shows, cancellations and reschedules.
2. Mark what was paid. Open your bank statement or payment app and match each payment to the right session.
3. Look at what's outstanding. Client by client, oldest first.
4. Send reminders. A short message with the dates and the total (see below).

On the last business day of the month, do a bigger check: total received, what rolls into next month and whether any client needs a conversation.

When a payment is late

Unpaid balances usually start small: one forgotten session, then another. The best fix is to follow up early, with precise information.

• Send facts, not feelings. "Hi Anna, the sessions on 10/01 and 10/08 are still open, $300 in total. Here's how to pay." It's hard to argue with dates.
• In writing. A message leaves a record and keeps the topic out of session time.
• With the agreement at hand. If there's a question about a late cancellation, what you agreed on settles it.
• Privately. A payment reminder is between you and the client, and no one else.

In Session Flow, on the Premium plan, the payment reminder comes ready for WhatsApp, with each outstanding session's date and the total. You review it and send it.

And the superbill?

Clients who see you out of network often ask for a superbill to request reimbursement from their insurance. Session Flow has a superbill template among its documents, along with receipts and attendance letters in PDF, with your details and the client's, on every plan. Check with each insurer which codes and details they require.