Common variations:
* Jonathan (most common spelling)
* Johnathan
* Jonathon
Less common variations:
* Jonahthan
* Jonathon (with a silent "h")
Other possibilities:
* Jonothan
* Jonathon (with a "y" instead of an "i")
* Jonathon (with a "k" instead of a "c")
It's important to note that these less common variations are not widely accepted and may be considered incorrect by some.
Ultimately, the best way to spell Jonathon is the way the person prefers.