I deal with 4 & 13 week TBills regularly.Suggest you use a regular Brokerage account for this activity.I have two securities set up in the Security List; US T Bill [4 wk] & US T Bill [13 wk].Create a category for the interest income; e.g., "Interest Gov Securities" and assign tax line item "Schedule B:US government interest" to this category.For the buy, use the Buy Bonds transaction.On maturity, use the Sell Bonds transaction.Enter the sell at the same price as the original buy; i.e., zero cap gains.Following the sell, enter the interest income (difference between face value and purchase/sale price) using the above interest category.I use the Memo field to record Treasury Directs ID code and the maturity date; e.g., "1AAEI 2018 11 08"; i.e., 1AAEI matures 11/08/2018.