The Client I Invoiced at the Wrong Rate for Four Months

It started because I was busy. That is always how it starts.

I brought on a new client in January. We agreed on a rate. I typed it into my brain and started working. I did not write it down anywhere that would talk to my invoices. I did not set it up in my billing tool. I just remembered it.

Except I did not remember it correctly.

What I Actually Charged

I had a standard rate I used for most clients. I had agreed to a slightly lower rate for this one because the volume was supposed to make up the difference. The volume materialized. The lower rate did not make it into my invoices.

For four months I invoiced this client at my standard rate. They paid every time without a word. I assumed this meant everything was fine.

It was not fine. It meant they had never checked.

In April I was doing a quarterly review. I was not even looking for problems. I was trying to figure out which client was most profitable so I could pitch them on more work. I pulled the agreed rate from an old email and compared it to what I had been charging.

The number was wrong. It had been wrong since January.

The Math Was Not Small

I had overcharged this client. Not by a rounding error. By a real number spread across four months of weekly invoices. When I added it up it was over $900.

I sat with that for a while.

I had to decide what to do. I could pretend I never found it. They had paid. They had never complained. Maybe they had agreed to the higher rate and I had misread the email. I went back and read it three times. I had not misread it. I had charged them more than we agreed.

So I issued a credit and sent an email explaining what happened. It was a bad email to write.

What the Time Tracker Revealed

Here is the part that still bothers me. My time tracker had the right rate attached to the project. I had set it up correctly when I created the project. But I was not using it to generate invoices. I was just using it to log hours. Then I was typing numbers into an invoice manually from memory.

The data was right. My process ignored the data.

When I started using Time-Trak to actually push time entries into invoices instead of treating them as two separate steps, this kind of error became impossible. The rate is set once on the project. The hours pull from logged entries. The invoice reflects what actually happened. There is no second place where a wrong number can sneak in.

The Client Did Not Fire Me

They were surprisingly decent about it. They said they appreciated me catching it and telling them. They kept working with me for another eight months.

But I thought about this a lot afterward. What if the error had gone the other way? What if I had been undercharging for four months and never noticed? That happens more often than overcharging. Freelancers round down, forget small sessions, skip logging a thirty-minute call. It adds up the same way, just in the wrong direction.

The Habit That Fixed It

I stopped treating rate management as something I held in my head. Every project now has a rate set at the start in the same system I use to track time. Invoice generation is not a separate creative exercise. It is a report based on actual logged entries.

I also check the rate on every project at the start of a new month. Takes two minutes. I look at the project, confirm the rate, confirm it matches the contract on file. That is it.

Four months of the wrong number because I trusted my memory over my own records. My memory was not trying to deceive me. It was just doing what memory does. My records would have held it correctly the whole time if I had let them.

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