Luum vs AdjustedCostBase.ca

This is the comparison where the honest answer is most often "use the other one, or use both." AdjustedCostBase.ca has been doing a single job since 2010, computing adjusted cost base for Canadian investors, and it does that job more completely than Luum does.

Luum is not an ACB calculator. It is a portfolio analytics product that tracks ACB as one of the records it keeps. Those are different tools, and the difference matters most in one specific place.

The short version

AdjustedCostBase.ca fits better if the cost-base calculation itself is what you came for, especially if you have sold at a loss and repurchased, or you want to work through option, bond or preferred-share cases carefully. There is a free tier and it does not expire.

Luum fits better if ACB is one of several things you need, alongside seeing every account in one view, allocation and drift against targets you set, fund look-through and fees, and you want the transaction history to arrive from your brokerage instead of being typed in.

The thing you should know before anything else

AdjustedCostBase.ca tracks superficial losses. Luum does not.

If you sell a security at a loss and buy it back inside the CRA's window, the loss is denied and gets added to the cost base of the repurchased units instead. That rule counts purchases in any account you control, including registered ones, and it extends to a spouse or a corporation you control, so it catches people who did not think they had done anything unusual. It is genuinely fiddly, and most institutions do not attempt it programmatically.

Luum does not apply the adjustment. Its capital gains figures do not account for the rule and the product says so wherever the number appears. AdjustedCostBase.ca lists superficial loss tracking as a feature.

So: if you have sold at a loss and repurchased within the window, they handle a case we hand back to you. That is not a close call and this page is not going to pretend otherwise. What the rule actually does is worth reading either way. Both CRA conditions, and the affiliated-person limbs that catch people who did not think they had done anything unusual.

What AdjustedCostBase.ca does well

It is focused, and the focus shows. A free tier with no time limit, guest access if you do not even want an account, foreign-currency handling, stock options, export to Excel or CSV, and, on the paid tier, spreadsheet import and ETF distribution-data import, which is the tedious part of getting return of capital right. That is one narrow problem worked since 2010, and there is no substitute for that kind of accumulated correctness.

It is manual: you enter transactions, or import them from a spreadsheet. There is no brokerage connection.

What Luum does differently

Luum starts from the portfolio rather than from the security. It connects read-only through Snaptrade. You authenticate on your own institution's page, Luum never holds your credentials, pulls the transaction history in, and computes ACB from it with the average-cost method, pooled across your accounts because that is how the CRA pools identical property. It applies return of capital and reinvested distributions automatically, converts foreign dispositions at the Bank of Canada rate for the trade date rather than today's, and names anything it could not account for on the report instead of quietly dropping it.

Around that it does the things a calculator has no reason to do. Every account lands in one picture, with allocation and drift measured against targets you set by asset class, region and sector, and a rebalance simulator that computes the trades which would close the gap. Realised gains are reported across every reportable account together, registered accounts excluded because their gains are sheltered, and the year's dispositions export as a T5008-style CSV. On the Investor tier and above, TFSA and RRSP contribution room is drawn down from the figure on your notice of assessment, flagging when you are near the limit and, separately, when you are over it.

The analysis layer goes further than the tax record. Luum looks through your ETFs to the securities they hold, attaches each fund's real management expense ratio and compounds that cost over ten, twenty and thirty years, detects pairwise overlap between two funds you own, and measures your home-country bias against the Canada weight in a global index. On the Wealth tier it quantifies blended risk from beta, volatility and maximum drawdown, scores concentration with the Herfindahl-Hirschman Index across four dimensions, compares your return against an index funded with your real contributions on the dates you made them, and runs a Monte Carlo projection of ten thousand simulated paths from your actual allocation on the capital market assumptions published annually by FP Canada and the Institute of Financial Planning, then says whether you are on track against your goal and what the gap is in today's dollars.

Ticker Scores rank what you hold on five measured dimensions nightly, watchlists carry optional price alerts, the Explore tab covers exchange-wide movers, 52-week highs and lows across the TSX, NYSE and NASDAQ and an IPO calendar, and an AI explains the numbers on your own screen in plain language, grounded in your real data and unable to invent a figure.

Luum's ACB figures are educational, are only as good as the transaction history behind them, and do not apply the superficial loss rule. Verify before you file.

Where they differ

Compared on	AdjustedCostBase.ca	Luum
What it is	A focused ACB and capital gains calculator	Portfolio analytics that keeps an ACB record
Superficial loss rule	Tracked	Not applied, handed back to you
How transactions arrive	Manual entry or spreadsheet import	Read-only brokerage sync, CSV, or manual
Free option	Free tier with no time limit	Free trial, then paid
Return of capital	Yes, with fund data import on the paid tier	Applied automatically
Pooling across accounts	Yes	Yes, one pool per security per taxpayer
Whole-portfolio view	No. It is a calculator	Every account in one view
Targets and drift	No	By asset class, region and sector
ETF look-through	No	Yes, MERs included

Where this leaves you

If what you need is the cost-base number, correct, including the awkward cases, and you are willing to enter the transactions. Use AdjustedCostBase.ca. It is free to start, it is older than we are, and on superficial losses it is simply ahead of us.

If ACB is one line item in a bigger question, what do I actually own across five accounts, what is it costing me, how far has it drifted from the plan, then a calculator will not answer that and Luum is built for it. Plenty of people reasonably use a focused calculator at tax time and a portfolio tool the rest of the year.

If you just want to run one security's pool through the arithmetic right now without signing up for anything, Luum's own adjusted cost base calculator is free and runs in your browser.

Common questions

Does Luum apply the superficial loss rule?

No. It keeps an adjusted cost base record on the average-cost method and does not make superficial loss adjustments. AdjustedCostBase.ca does track that rule, and if it applies to your situation that is a decisive reason to use a tool built for it.

Can I use both?

Yes, and for a taxable account with frequent trading that is arguably the better setup. Use the dedicated calculator for the cost base arithmetic and Luum for portfolio analysis, performance and the cross-account view.

Which should I use if I only need cost base tracking?

AdjustedCostBase.ca. It does one job thoroughly, including the rule Luum does not apply, and if that job is all you need then a portfolio analytics product is more than the problem requires.