Once your Offer in Compromise (OIC) is accepted, it's time to act. Fulfill the terms of the offer – usually a 5-month cash month offer or 24-month periodic payment plan. Ensure timely filing and payment of future tax returns; extensions aren't allowed. You must file and pay all future tax returns on time for the next 5 years, no extension allowed. If your OIC is canceled due to any of the stated above, you will be liable for the entire obligation with added interest and penalties.