> For the complete documentation index, see [llms.txt](https://docs.fieldmotion.com/fieldmotion-api-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fieldmotion.com/fieldmotion-api-docs/customer/_gethighestaccountnumber.md).

# \_getHighestAccountNumber

Returns the highest Account Number being used by an existing Customer.

### Example

```
FM_api('Customer_getHighestAccountNumber');
```

### Result

#### On Success

```
"99996"
```

In this result, there were 2 Customers, with the Account Numbers "367" and "99996".

#### On Failure

If there are no existing Customers:

```
false
```

If there are existing Customers, but none of them have Account Numbers set:

```
""
```