Yes, you do have to report all your items on Form 1099-B on your tax return; the fact that basis is not listed doesn't except it from the reporting obligation. The brokerage firm may not know the cost basis of a security transaction and therefore is not able to report it to the IRS, but you have to report it and provide that basis information from your own records.
Form 1099-B: Proceeds From Broker and Barter Exchange is a federal tax form that itemizes a taxpayer's gains or losses in every transaction made over the course of a tax year. The broker or barter exchange must mail a copy of the form to all clients by January 31st of the year following the tax year.
Taxpayers transfer the information from Form 1099-B to Form 8949 to calculate their preliminary gains and losses. The result is entered onto Schedule D of the tax return.
Answers are correct to the best of my ability but do not constitute legal or tax advice.
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