A missing 1099-B usually still exists. The broker files it with the IRS and makes the recipient copy available, often inside a consolidated statement. Ask the client to download it from the account online, then check the old broker if the account moved. If cost basis is blank, purchase records fill the gap. Guessing the figures is the last resort.
Where the 1099-B figures live if the paper never came
The figures on a Form 1099-B exist whether or not the paper copy reached the client. A broker files Form 1099-B with the IRS for each person with reportable sales, so the same figures sit in the client's account records. The usual places are the account's online tax documents, a consolidated year-end statement, and the monthly statements.
The IRS page about Form 1099-B says a broker or barter exchange must file the form for each person with sales of securities for cash and certain other transactions. That means the broker has produced the figures, even if the client never opened the envelope or the email that announced them.
Most clients do not get a standalone 1099-B. The General Instructions for Certain Information Returns (2025) mention statements furnished as part of a consolidated reporting statement, a single document that can combine a 1099-B with the 1099-DIV and 1099-INT for the same account. A client who says "I got my 1099-DIV but no 1099-B" may be looking at the same document without realizing the sales section starts on page 6.
Before asking the client for anything, check the date. For tax year 2025, the 2025 General Instructions say Form 1099-B and consolidated statements had to be furnished by February 17, 2026, later than most other 1099s. A brokerage form missing in early February may simply not be due yet; when do 1099s arrive lists each form's date.
Step list: retrieving a missing 1099-B
Each step names what to ask the client for. Stop when the form is in hand. The example client is fictional.
- Search the folder first. Open every file the client has sent from the brokerage and look for a sales or "proceeds from broker transactions" section. Ask the client for nothing until this is done.
- Ask for an online download. Ask the client to sign in to the brokerage account, open the tax documents area, and download the full year-end tax PDF for the tax year. Ask for the whole file, not a screenshot of one page.
- Ask about every account at that broker. A client can hold a taxable account, a joint account and an IRA at one broker. Ask for a list of account numbers, so a form for account XXXX-4821 is not mistaken for one for XXXX-7310.
- Ask whether the account moved during the year. If it did, ask for the old broker's name and the final statement from the old account. The next section explains why.
- Ask for December and monthly statements. If no tax form is available yet, monthly statements show trades, dates and amounts. They help build an estimate, but they are not a substitute for the form.
- Ask the client to call the broker. If the form cannot be found online, ask the client to call the broker, confirm the address and email on file, and request a copy. Note the date of the call in the client's log.
For a fictional client, Lena Moreau of Example Accounting, step 3 might show a joint account at Ridgeline Brokerage that sold shares in March, with no form in the folder because it went to the spouse's email.
Missing brokerage statement for taxes when an account moved
A missing brokerage statement for taxes is common when an account moved from one broker to another during the year. The broker that handled a sale is the one that files the 1099-B for it, so sales made before the transfer can appear on a form from the old broker, sent to an address the client no longer checks.
The transfer itself can affect the new broker's form. The Instructions for Form 1099-B (2026) say a person who transfers custody of a specified security to a broker must give that broker a written transfer statement within 15 days after settlement. If a complete transfer statement is not furnished, the receiving broker may treat the security as noncovered, which affects whether it reports basis. If a transfer statement arrives later showing a covered security, the broker must file a corrected 1099-B within 30 days, unless the statement arrives more than three years after the original filing.
In practice this means two things for the firm. First, the expected-documents list for a client whose account moved should carry two brokerage lines, one per broker, each with its own issuer name. The post on tracking missing client documents explains why each expected line names its issuer. Second, a form from the new broker that shows no basis for transferred shares may be followed by a corrected form. What to do when a corrected form arrives after the return is filed is covered in corrected 1099 after filing.
Closed accounts raise the same question. If a client closed an account partway through the year and sold shares before closing it, ask for the closing statement, the old login if they still have one, and any tax form the old broker issued for that year. A closed account can leave a form behind that nobody thinks to look for, because the client no longer reads that broker's mail.
What if cost basis is missing from the 1099-B?
Cost basis missing from a 1099-B usually means the shares are noncovered securities, for which the broker may leave basis blank. The form then shows proceeds without basis, and the basis has to come from the client's own purchase records, such as old trade confirmations, statements from the year of purchase, or records from a previous broker.
The Instructions for Form 1099-B (2026) define a noncovered security as any security that is not a covered security, and give stock acquired for cash in an account after 2010 as one example of a covered security, with an exception for stock eligible for the average basis method. For a noncovered sale, the broker may check box 5 and leave boxes 1b, 1e, 1f, 1g and 2 blank. Box 12 shows whether basis was reported to the IRS.
Where to find the basis:
- The account's position detail. Ask the client whether the account's online lot or position detail shows an acquisition date and cost for the older shares, even though the form does not report them.
- Trade confirmations and old statements. The client's own files from the year of purchase.
- The previous broker. If the shares were transferred in, the old broker may hold the purchase history.
- Gifts and inheritances. Shares received rather than bought follow different basis rules. The IRS tax topic on basis of assets says basis for purchased stock is the purchase price plus costs such as commissions, and points to other publications for property received another way.
Finding purchase records can take weeks, which is one reason an unknown basis sometimes leads to an extension. That trade-off is covered in filing an extension because of missing documents.
Can a return be filed without the 1099-B?
A return can be filed without the 1099-B in hand, but the sales still have to be reported, and the broker has already sent its figures to the IRS. Filing from monthly statements or memory risks a mismatch with what the broker reported. That is the case for treating the form, not an estimate, as the source for brokerage sales.
The Instructions for Form 8949 (2025) say to report sales even if no Form 1099-B was received. Those sales go in Part I with box C checked for short-term transactions, or Part II with box F for long-term ones, with net proceeds in column (d) and the correct basis in column (e). Sales that did come with a 1099-B go under box A or D when basis was reported to the IRS, and box B or E when it was not.
The risk is in the numbers. A client's memory of "about $40,000 in sales" is not what the broker reported. Monthly statements show trades but may not reflect the same adjustments the form does, such as the wash sale amounts covered in the next section. A return built from statements and later contradicted by the actual form usually leads to an amended return.
The same reasoning applies to other forms that arrive late from a third party. A partnership K-1 is the most common case, and the timing and options for it are in when a K-1 arrives late.
1099-B edge case: wash sales and adjustments on the form
Wash sales and other adjustments shown on a 1099-B change the reportable gain or loss, so those boxes must be read from the form itself. Box 1g reports a wash sale loss that is not allowed. Box 1f reports accrued market discount. Box 2 shows whether the gain is short-term or long-term, and whether it is ordinary.
The Instructions for Form 1099-B (2026) describe box 1g as the amount of wash sale loss disallowed and say the basis of the replacement shares is increased by that amount. The Instructions for Form 8949 (2025) say to use adjustment code W for a nondeductible wash sale loss, entered as a positive number in column (g), and to enter the correct amount if the box 1g figure is wrong. They also give code B for a basis that is wrong on the form: for sales with basis reported to the IRS, the reported basis goes in column (e) and the correction goes in column (g).
Common errors with these boxes:
- Using the summary page only. A consolidated statement's summary may total proceeds and basis without showing per-lot adjustments. Read the detail pages.
- Retyping basis from a monthly statement. The statement may show the original cost, while the form's basis reflects a wash sale adjustment.
- Treating a corrected form as a duplicate. A second consolidated statement for the same account may be a corrected copy with different adjustments. Compare the two before setting one aside.
Schema CPA reads 1099 series forms, including 1099-B, as their own documents, and flags a brokerage form that came in last year and has not arrived this year; the client tracker demo shows that flag beside each missing item. More on individual tax forms is in the tax forms and payroll category.