Okay so let us get technical. No you can never make too much money for PSLF. However your income can cause you to not ever have a payment that qualifies for the plan.
In order to qualify you must either be on one of the Income Driven Plans or a plan that is equal to or greater than the payment on a 10-year standard. The second one instantly leaves nothing left to forgive thus leaving the program ineffective meaning the only effective way to apply for PSLF is through an Income Driven Repayment plan.
This of course is driven by your income. If you make too much money and are not able to qualify for one of these plans you will never be able to get a qualifying payment. As an obvious result, you will not be able to reach the 120 qualifying payments without paying your loan off first.
So if you are in this boat what should you do? Well first off you do not have to apply for the plan in case your situation changes later. If you are making qualifying payments on a plan that is equal to or greater than a 10-year standard and you later qualify for a Income plan, once you send in your application to be considered for PSLF, all your qualifying payments will be counted during the eligible time period (which begins October 1, 2007).
The reason for this is this plan is designed for those who are in public service but not making a lot of money. As a result it does leave out those who make over a threshold in theory even if technically they are not excluded.
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