A good rule of thumb: Call as early in the morning as possible. Phones are open from 7 a.m. to 7 p.m. (your local time) Monday to Friday, except: Residents of Hawaii and Alaska should follow Pacific time.
You may qualify to apply online if: Long-term payment plan (installment agreement): You owe $50,000 or less in combined tax, penalties and interest. You have filed all required returns. Short-term payment plan: You owe less than $100,000 in combined tax, penalties and interest.
Contact an IRS customer service representative to correct any agency errors by calling 800-829-1040 (see telephone assistance for hours of operation).
You can send Form 9465 with the e-return, but the IRS must still approve the installment agreement form.
Or: For individual tax returns, call 1-800-829-1040, 7 AM - 7 PM Monday through Friday local time. The wait time to speak with a representative may be long. This option works best for less complex questions.