Is Your Portfolio Too Concentrated? Understanding Your Risk Score

Published June 19, 2026 · 7 min read · By the WealthWise team · Updated June 20, 2026

Most Canadian investors know diversification matters — but far fewer realize their portfolio might be dangerously concentrated without showing any obvious warning signs. You might hold five ETFs and still have 40% of your money riding on a handful of US mega-cap tech stocks. WealthWise's concentration risk score is designed to surface exactly that kind of hidden exposure, giving you a clear, actionable number instead of a vague feeling that something might be off.

What Is Portfolio Concentration Risk?

Concentration risk is the danger that comes from having too much of your wealth tied to a single stock, a single sector, or a single country. When that one position moves sharply against you, the damage to your overall portfolio is disproportionate — because there isn't enough diversification to cushion the blow.

The risk shows up in two distinct forms:

• Single-stock concentration: One company represents an outsized share of your portfolio. This is common among employees who hold company shares, investors who rode a winner (like a Canadian bank or a tech name) for years without trimming, or traders who are making a concentrated bet.
• Overlapping ETF concentration: You hold multiple funds that each look diversified on the surface, but share many of the same underlying holdings. Buying VFV, XIU, and a broad North American ETF together sounds diversified — until you notice they all hold the same Shopify, the same Apple, and the same Microsoft positions.

The insidious thing about the second type is that it's completely invisible from the fund names alone. You need to look through each ETF to its actual underlying constituents before you can see what you truly own.

How WealthWise Calculates Your Risk Score

WealthWise computes your concentration risk score by performing a look-through analysis of every position in your portfolio — including ETFs. Rather than treating an ETF as a single holding, the tool decomposes it into its actual underlying stocks and sectors, weighted by the ETF's real top-holdings data. This means two things happen simultaneously:

• Individual stock positions and ETF-derived stock exposures are aggregated into a single view of your true equity holdings.
• The tool identifies where those holdings cluster — by stock, by sector (Technology, Financials, Energy, etc.), and by geography (Canada, US, International).

The resulting score reflects how much your returns would be impacted by a shock to a single concentration point. A lower score indicates a more broadly diversified portfolio; a higher score signals meaningful concentration somewhere in the stack that warrants attention.

The score is not a prediction of future returns — it's a structural diagnostic. Think of it like a blood-pressure reading: it doesn't tell you when the problem will happen, but it tells you whether your portfolio is in a healthy range or carrying elevated risk.

Reading the Score: What the Ranges Mean

WealthWise presents the concentration risk score alongside a breakdown of where the concentration actually lives. You'll see:

• Top holding weight: The single largest position (or aggregated exposure) as a percentage of your total portfolio. Anything above roughly 10–15% for a single stock warrants a closer look.
• Sector concentration: Whether one sector — most commonly Technology for Canadian investors holding US-heavy ETFs — dominates your allocation well beyond what a global-market-weight portfolio would imply.
• Geographic concentration: The split between Canada, the US, and international markets. Many Canadians are surprised to learn how US-heavy even "Canadian" all-in-one ETFs can be, or conversely, how much home-country bias still lurks in manually assembled portfolios.

A portfolio of genuinely diversified all-in-one ETFs like XEQT or VEQT will score well because the geographic and sector exposure is already spread broadly by design. A portfolio of three overlapping US-focused ETFs plus a few individual tech names will score poorly — even if the account balance looks large and the fund names sound different.

For a deeper look at how the sector look-through works under the hood, see our guide on ETF sector breakdown and look-through analysis.

The Hidden Danger: ETF Overlap

ETF overlap is one of the most common — and most underappreciated — sources of concentration risk for Canadian DIY investors. Consider a simplified example:

Hold all three in equal weight and you haven't diversified — you've tripled down on the same handful of mega-cap US technology companies. A sharp drop in that cluster hits every one of your funds at the same time, for the same reason. WealthWise's overlap detection aggregates these positions across your entire account roster (TFSA, RRSP, non-registered) to show you the real picture.

To understand how geographic exposure is derived from actual ETF holdings data, see our article on geographic exposure in Canadian ETF portfolios.

Why This Matters More Than You Think

Concentration risk becomes most dangerous precisely when markets are stressed — the moments when you most need your diversification to hold. During a sector selloff or a country-specific shock, correlated positions fall together. A well-diversified portfolio doesn't avoid losses, but it avoids the kind of catastrophic drawdown that forces investors to sell at the worst possible time.

For investors using a benchmark like the S&P 500 for comparison — which WealthWise supports through Modified-Dietz time-weighted returns — concentration in US tech can actually create benchmark-hugging behaviour where you think you're diversified but you're really just tracking the index with extra fees and lower liquidity. See our piece on comparing your portfolio to the S&P 500 for more on how that benchmark comparison works.

How to Use the Score to Improve Your Portfolio

The risk score is most useful as a conversation starter with yourself. When you see a high score, the right next question is: is this intentional concentration I'm comfortable with, or is it accidental overlap I didn't realize was there?

Some common actions Canadian investors take after reviewing their risk score:

• Consolidate overlapping ETFs: Replace three partially overlapping US funds with a single broad-market or all-in-one fund. Simpler, cheaper, and genuinely more diversified.
• Trim a single-stock winner: A position that has grown to 15–20% of your portfolio through appreciation deserves a deliberate decision — hold it intentionally or trim it back toward your target weight.
• Add international or sector diversity: If your score flags heavy US Technology concentration, adding broad international exposure (Europe, emerging markets) dilutes that single-factor risk.
• Review across all accounts: WealthWise aggregates across your connected brokers (via SnapTrade read-only sync) and manually imported accounts — because concentration that looks fine in one account can be severe when you view the household total.

WealthWise: Free Concentration Analysis for Canadian Investors

WealthWise is an independent Canadian analytics platform for portfolios held at Wealthsimple, Questrade, Disnat, and other Canadian brokerages. It does not execute trades and has no access to your login credentials — the broker sync uses SnapTrade's read-only connection, which means WealthWise can see your holdings but cannot move your money.

The concentration risk score is part of the core analysis suite, available to all users at no cost. It works whether you've synced your broker directly, imported a CSV from your brokerage, or entered holdings manually. For investors who want to track dividends, run DRIP simulations, compare their returns to a benchmark, or monitor their progress toward a passive income goal, all of those tools live in the same free dashboard.

If you're building or reviewing a portfolio and want to understand where your real risk lies — not just the fund names but the actual underlying exposures — the concentration risk score gives you that picture in seconds.

Frequently asked questions

What is a good concentration risk score in WealthWise?

There's no universal threshold — the right score depends on your investment strategy and risk tolerance. A portfolio of diversified all-in-one ETFs like XEQT or VEQT will naturally score better than one with multiple overlapping US-focused funds or large single-stock positions. The score is most useful as a relative diagnostic: if it's high, investigate where the concentration lives and decide if it's intentional.

Can I have concentration risk even if I hold multiple ETFs?

Yes, absolutely. ETF overlap is one of the most common hidden sources of concentration risk. If your ETFs share the same underlying stocks — particularly US mega-cap technology companies — holding more funds doesn't reduce your exposure to those names. WealthWise's look-through analysis aggregates the underlying holdings across all your ETFs to reveal the true picture.

Does WealthWise look at holdings across all my accounts?

Yes. WealthWise aggregates positions across all connected and imported accounts — TFSA, RRSP, non-registered, and others. This is important because concentration that looks acceptable within a single account can be significant at the household level, particularly if the same ETFs appear across multiple accounts.

Is a concentrated portfolio always bad?

Not necessarily. Concentration is a choice some investors make deliberately — for example, holding a large employer stock position or making a high-conviction sector bet. The risk score doesn't tell you what to do; it tells you where your risk is. The key question is whether the concentration is intentional and understood, or accidental overlap you didn't realize was there.

How does WealthWise get the underlying holdings of my ETFs?

WealthWise derives sector and geographic exposure from each ETF's real top-holdings data, using a look-through approach that also handles ETF-of-ETFs structures. Geographic exposure is derived from the underlying holdings weighted by fund allocation rather than the ETF's stated mandate, which gives a more accurate real-world picture.