Features

The done-for-you Form 1099-DA reconciliation service

BasisBridge is the done-for-you Form 1099-DA reconciliation service — we rebuild the cost basis your broker left blank, tie every sale to its evidence, and hand you (or your CPA) a Form 8949-ready pack. Records reconciliation only — never tax advice, never filing.

What BasisBridge does for you

Every disposal reconciled, every figure evidenced

Reconcile — $149 one-time

Up to 500 disposals, 1 tax year, FIFO reconstruction + variance check + 8949-ready workbook.

Reconcile + Evidence — $349 one-time

Up to 2,500 disposals, Full evidence index, Transfer-in tracing, CPA handoff memo, Priority turnaround.

CPA Desk — $79 /mo

Rolling reconciliation desk for CPA/tax firms, Client packs monthly, Exception queue managed for you — client packs monthly, exception queue managed for you.

The engine

FIFO lot matching per asset, per account — lot pools are never co-mingled across accounts/wallets. A disposal whose 1099-DA basis is blank gets its basis reconstructed from acquisition lots (FIFO_RECONSTRUCTED); a reported basis is used as-is (BROKER_REPORTED) and flagged BASIS_MISMATCH when it differs from the FIFO figure by more than $1. Term is short/long from the earliest consumed lot (> 365 days = long).

The pack

The deliverable, typeset as a ledger

01Disposal-by-disposalProceeds ↔ basis ↔ gain/loss with short/long split
02Variance checkThe 1099-DA total variance check — proceeds tied to the dollar, or the variance explained
03Exception listThe missing-basis exception list — nothing silently zero-based
04Transfer-in tracingTransfer-in tracing notes — the transfer date is never used as the acquisition date
05Evidence indexEvery basis figure points at its source record
FlagMISSING_BASISBlank basis on the form — reconstructed from acquisition lots (FIFO_RECONSTRUCTED) or flagged when lots are short.
FlagINSUFFICIENT_LOTSLots short — the basis is left blank and flagged, never zero-based or partially invented.
FlagBASIS_MISMATCHReported basis differs from the FIFO figure by more than $1.
FlagTRANSFER_IN_UNMATCHEDDisposal sourced from a transfer-in — the transfer date is never used as the acquisition date.

Records reconciliation only — not tax advice, not a tax return.

How it works

From messy CSVs to a pack your CPA can file from

1

Send your files

Send your exchange CSV exports + your 1099-DA totals (secure intake list provided after checkout — never send passwords or API keys).

2

We run the reconciliation

We run the reconciliation engine + a human exception review: every blank-basis sale FIFO-reconstructed, every mismatch and transfer-in flagged with its evidence.

3

You get the pack in 5 business days

You get the pack in 5 business days: 8949-ready workbook, exception list, evidence index, and a one-page CPA handoff memo.

Questions

The FAQ, verbatim

Do you file my return?

No. Records reconciliation only; we are not a CPA firm and give no tax advice.

What method?

FIFO by default, per account, documented in the pack. If your records support a different lot method you've consistently used, note it at intake and we reconcile on that basis and label it.

What about DeFi / self-custody sales with no 1099-DA?

Include the wallet exports; disposals with no broker form are reconciled and listed separately so nothing is silently dropped.

Security?

CSVs and forms only — never passwords, seed phrases, or API keys. Files deleted from working storage 30 days after delivery (retention note in the pack).

What if my records are incomplete?

You get the exception list showing exactly which evidence is missing per lot — that list alone is the roadmap to closing the gap.

Your 1099-DA shows what you sold. Rebuild what you paid.

Flat price. No API keys to hand over. No software to learn. The pack in 5 business days — proceeds tied to your 1099-DA total, to the dollar, or the variance explained.

Reconcile — $149See what’s in the pack