Wash-Sale Tools: Compare Guidance, Trade Controls, and Tax Records

Updated September 26, 2026.

Choose a wash-sale tool for the part of the process you need help with: understanding a proposed sale, controlling trades, or reconciling the resulting tax records. Mezzi provides financial guidance using available account information and personal context. RedBlack supports professional investment management and trading controls. TradeLog specializes in trade accounting and tax reporting. They solve different problems.

The most important question is what the tool can see. A sophisticated check can miss a purchase in an account that was never included. An AI explanation can be useful without constituting a completed wash-sale calculation. A tax report can identify an adjustment after a trade without preventing that trade beforehand.

How we compared: Mezzi publishes this guide. We reviewed official product documentation, prices, and IRS guidance on September 26, 2026, alongside our Mezzi application review. We did not execute trades across these products or measure a prevention success rate. This is a workflow comparison, not a claim that any tool guarantees compliance or tax savings.

Compare the three workflows

The tool with the most automation is not automatically the right purchase. An individual with a few proposed sales may need a clear review process. A trading firm needs controls inside its operating workflow. An active trader preparing a return needs accurate transaction accounting. For a broader software-selection guide, see wash-sale tracking software.

What a wash-sale review must cover

Under IRS Publication 550, a wash sale can arise when stock or securities are sold at a loss and substantially identical stock or securities are acquired within 30 days before or after the sale. Certain contracts and options also matter. Looking only at purchases after the sale leaves part of the window unchecked.

The IRS also addresses purchases by a spouse or controlled corporation and acquisitions in an IRA or Roth IRA. A broker's Form 1099-B does not necessarily capture every adjustment the taxpayer must make. The absence of a reported wash sale is therefore not proof that no wash sale occurred.

For a typical taxable-account replacement purchase, the disallowed loss is added to the replacement holding's basis, postponing the deduction. The IRA case does not receive that same basis adjustment. The facts of a particular transaction matter; this overview is not a substitute for resolving a complicated case with a qualified tax professional.

A different ticker is not a universal safe harbor. The IRS uses a facts-and-circumstances standard for substantially identical securities. Do not let a product's simplified matching rule become an unsupported legal conclusion about every fund, option, or substitute investment.

1. Mezzi: connect the proposed sale to your financial priorities

Mezzi is relevant when the question begins with an investment decision: whether to realize a loss, how a proposed change affects the rest of the portfolio, or what information you should gather before acting. Its broader view can include investments, banking, other assets such as real estate, and liabilities. AI Personalization lets you provide goals and constraints that help frame the discussion. See the account-category update.

That context is useful because a sale is rarely only a tax question. You may be preserving cash for a home purchase, reducing an employer-stock concentration, or trying to avoid disrupting a long-term allocation. Describing those priorities can make an investment discussion more relevant than asking whether a position is simply up or down.

A productive starting prompt is: “Help me identify the information needed to review this proposed loss sale. Distinguish the account data available here from transactions or automatic purchases I still need to check.” Then identify the particular account, security, intended transaction, and relevant outside activity. Treat a missing input as a task to resolve, not as evidence that no conflict exists.

What Mezzi should not be assumed to do: This guide does not verify a universal real-time wash-sale prevention engine, complete tax-basis accounting across every institution, or an order block at your broker. Available tax lots and history depend on the connection and the data supplied. Guidance does not execute the transaction. A preference entered in AI Personalization is not proof that an external broker's reinvestment setting has changed.

Current pricing includes free access, Advisory at $399 annually, and Concierge at $999 annually. Compare the included guidance and service scope with your needs rather than treating the subscription as a guaranteed tax-saving investment. No hypothetical harvested loss should be counted as money earned merely because it exceeds the annual fee.

Best fit: You want help relating a proposed investment action to your broader finances and identifying the next questions to resolve. Choose a different or additional workflow when the required output is a reconciled tax-reporting file or professional trade-control system. Mezzi can have a useful role without replacing those specialized functions.

2. RedBlack: controls for professional investment teams

RedBlack's current rebalancing and trading platform is built for RIAs and wealth managers. It combines portfolio management with order management and pre- and post-trade checks. This is operational software for teams managing portfolios, rather than a retail app selected only for a household dashboard.

Its investment-management documentation describes household and family wash-sale detection, tax-lot decisions, tax-loss harvesting, and substitute-investment controls. Those capabilities deserve direct credit. It would be misleading to describe professional trading software as merely a basic tracker or to imply that Mezzi is the only product considering multiple accounts.

For a firm, the key evaluation is how those controls behave within its actual operating process. Ask which accounts enter a household, how ownership relationships are represented, what happens when transaction data arrives late, and which restrictions carry from a proposed trade into the order workflow. A family label on a screen is not enough to establish that every relevant relationship has been configured correctly.

Use a demonstration with a concrete scenario. A taxable account has a proposed loss sale; another included account has a recent purchase; an automatic purchase is scheduled elsewhere. Ask the vendor to show which events are detected, what appears to the operator, and what remains outside the system's knowledge. This is a proposed buyer test, not a test we claim to have performed.

The reviewed product page offers a demo and contact route rather than a standard public subscription price. Request a written quote covering implementation, data connections, training, ongoing support, and the relevant trading modules. A firm should compare the total operating cost with its current process, not compare an undisclosed enterprise contract directly with a consumer-app annual fee.

Best fit: A professional team needs coordinated portfolio implementation and controls. Less suitable: An individual principally wants an explanation of a few tax-sensitive decisions and does not operate an advisory trading workflow. Do not buy enterprise complexity solely because the feature list is longer.

3. TradeLog: reconcile the actual trades and tax adjustments

TradeLog is a specialized trade-accounting product. Its official overview and pricing describe a Windows application that combines brokerage history, including IRA activity, in a tax-year file. It imports trade records, supports wash-sale adjustments, and produces reporting used in tax preparation. That is a more specific job than an AI conversation about a portfolio.

The initial annual prices are $219 for Investor, with up to 1,500 trade records; $359 for Trader, with up to 5,000; and $459 for Elite, for more than 5,000. Eligible renewal prices are lower. Each subscription includes one file key; additional keys are $79. The 30-day trial permits importing and previewing, but finalized reporting and certain exports remain restricted.

Plan selection requires counting records correctly. TradeLog's subscription FAQ explains that a buy or sell is a record and partial fills can add records. One hundred round-trip trades may therefore involve at least 200 records. Do not equate a brokerage's count of completed trading ideas with the subscription's transaction limit.

The work is in the records as much as the software. Prepare starting positions, import the relevant history, identify missing or duplicate transactions, and review the resulting holdings and proceeds against the source records. A reconciled output is more valuable than an impressive-looking report created from an incomplete file. Retain the supporting records so a preparer can understand why an adjustment appears.

TradeLog also documents file-specific wash-sale settings, including assumptions for option transactions. Review those settings with someone who understands your transactions. A configurable matching approach should not be presented as the IRS's definitive treatment of every possible security combination.

Best fit: You actively trade and need a detailed accounting and reporting workflow. Less suitable: You only want a broad financial overview, do not need trade-level records, or expect a tax application to execute or block orders at an unrelated broker. Confirm system requirements, supported imports, and the work involved before subscribing.

A simple example: loss, adjustment, and eventual reporting

Suppose you buy 100 shares for $10,000, sell all 100 for $8,000, and buy 100 identical shares in a taxable account for $8,500 within the wash-sale window. Ignoring fees and other transactions, the realized loss is $2,000. If the wash-sale rule applies to the full transaction, that loss is disallowed currently and added to the replacement shares' basis, producing a $10,500 basis.

The example illustrates why “I sold at a loss” and “I have a deductible loss this year” are different statements. It also shows why an account balance alone cannot establish the tax result. Quantity, dates, basis, replacement purchases, and account type all matter.

Do not apply that taxable-account basis example to an IRA replacement purchase. The IRS specifically distinguishes that case. Partial replacements and more complex trading sequences also require additional matching rather than simply copying the full-loss arithmetic above.

Use a three-stage review before relying on automation

Before the proposed sale: Identify all relevant accounts, ownership relationships, recent purchases, reinvestments, and scheduled activity. Establish which information your chosen tool contains and which facts must be checked elsewhere. Record uncertainties rather than converting them into a clean bill of health.

During the decision and implementation: Review the trade's investment purpose as well as its tax implications. Confirm who will place the order and who controls recurring purchases. An explanation, an alert, and an order restriction are distinct outputs. Make sure the output you need is actually part of the selected product.

After the transaction: Retain confirmations and monitor relevant subsequent activity. Reconcile tax reporting with complete records and resolve discrepancies. A pre-trade review is not a reason to skip the later accounting, especially when new transactions can affect the result.

This process gives each tool a clear role. It also makes it easier to decide whether you need one service or several. Buying overlapping dashboards may add little; combining relevant guidance with the accounting or trading controls your circumstances require can solve different parts of the problem.

Frequently asked questions

Can AI guarantee that I avoid wash sales?

No. A result depends on complete information, the applicable rules, and what the system actually does. An explanation is different from a trade restriction or a reconciled tax calculation. Missing outside transactions can change the conclusion.

Does the wash-sale window start after I sell?

No. IRS guidance covers relevant acquisitions within 30 days before or after the loss sale. Reviewing only future purchases leaves the earlier part of the window unchecked.

Is TradeLog the same kind of tool as Mezzi?

No. TradeLog specializes in trade accounting and tax-reporting records. Mezzi provides financial guidance using available account information and personal context. The appropriate choice depends on whether you need decision support, reconciled reporting, or both.

Is a clean Form 1099-B proof that no wash sale occurred?

No. The IRS says a wash-sale loss can be nondeductible even when it is not reported on Form 1099-B. Review the relevant transactions and account relationships rather than relying solely on the absence of a broker-reported adjustment.