I successfully claimed back extra tax paid during 2007 even though our family income was below 120k. I realized that I had been taxed me at source at the wrong rate all year. I had to submit a form before March 31st of the next year (2008), and was reimbursed during August 2008. When I went into the local tax office in Lausanne to get the forms in late March, the secretary I spoke to called someone down to meet me, who took me to a private meeting room and explained everything that I needed to know to complete the forms and make the application. I was very impressed with the service I received (and with myself for being able to do it all in French ). Hopefully something similar is possible for you, and if you're lucky then you may find an equally helpful person in your local tax office.