Unless it's an especially large check from a foreign source, you don't have to report personal check deposits to the Internal Revenue Service. However, if you deposit more than $10,000 in cash, you will need to complete and submit a tax form within 15 days. Taxpayers who have large foreign bank accounts also have to submit information to the IRS on an annual basis.
Large Cash Deposits
Taxpayers that receive more than $10,000 in cash from a single transaction are required to report the deposit to the IRS. Even if you receive more than $10,000 through several installments, you still have to report it if the deposits are all related to one transaction. For example, if you perform a service and require a $6,000 cash down payment and $6,000 when the job is complete, you should report it as one $12,000 transaction.
The IRS defines cash as currency, bank drafts, cashiers checks travelers checks and money orders, so you don't have to fill out this form for personal or business checks over $10,000, or for direct deposits over $10,000.
Reporting Requirements over $10,000
Taxpayers should report cash payments in excess of $10,000 on Form 8300 and submit the form to the IRS within 15 days of receiving the payment. You'll need to identify who you received the cash from and the method of payment, and provide a description of why you received the money. Your bank is also required to report cash deposits over $10,000 so the IRS could take notice if there's a discrepancy in your report or if the form is filed late.
Reporting Foreign Gifts
Although taxpayers do not need to report gifts from domestic sources, they do have to report gift deposits from foreign persons and businesses that exceed a certain level. You must fill out Form 3520 if you receive more than $100,000 from foreign people and estates, or if you receive more than $13,258 from foreign corporations or partnerships.
Gifts include monetary gifts such as cash and check deposits, along with non-monetary gifts like a car or jewelry. If you receive a physical asset in addition to a check deposit, the value of a non-monetary gift is the item's fair market value on the date you received it. When calculating gift amounts, aggregate all gifts from foreign sources. For example, if your foreign uncle and aunt gave you $60,000 apiece, you need to complete the form. Form 3520 is due the same date as your annual tax return.
Foreign Bank Accounts
Along with reporting foreign deposits, you might need to inform the IRS about the current balance of your foreign bank accounts. You must complete a report of foreign bank and financial accounts -- referred to as an FBAR -- if the aggregate balance of your foreign accounts ever exceeds $10,000 during the year. For example, if your foreign bank account had a balance of $11,000 in July but the balance was reduced to $4,000 in December, you still need to complete the form. Complete your FBAR by June 30 of the following year using FinCEN's e-filing system.