The question
"I own three different funds. Am I as spread out as I think?"
The idea
- An ETF is a basket (What an ETF is). When you own several baskets, the same companies can sit in more than one. Look-through means adding up what you own underneath the funds, company by company: your dollars in each fund times that company's weight (its percent of the fund).
- Concentration is a large share of your money riding on one company or one sector (an industry group, such as technology). Look-through finds it, and it grows when you also own a company's shares directly, for example through an employer plan.
Worked example
The 4 steps beside the drawing at the top work this through on ETFIQ data. Point at a step to light the part of the drawing it describes.
Jordan has $200,000: $100,000 in SPY (S&P 500), $60,000 in QQQ (Nasdaq-100) and $40,000 in XLK (technology). Every weight below is from the funds' own books, dated Nov 9, 2026.
Total: $19,468, or 9.7% of Jordan's money. In SPY alone, Apple was 7.86%.
These three companies make up $51,292, or 25.6% of the $200,000.
Three tickers looked like three choices. Underneath, a quarter of the money rode on three companies, and more than half on one sector.
The common mistake
"More funds means more spread." Not if they hold the same things. Jordan's three funds share their three largest companies. Adding XLK to SPY and QQQ added more of what Jordan already owned. The Overlap tool, /etf-overlap/, shows how much two funds share before you add one.
Check your understanding
Pick an answer to see why. Two of three right passes the lesson.
1. What does look-through add up?Answer: C. Your dollars in each company or sector, across all your funds. look-through goes under the funds to what they hold. Not D: the largest holding in one fund misses the same company sitting in your other funds.2. Lee has $50,000 in a fund where a company is 10% and $50,000 in a fund where it is 4%. How much of Lee's $100,000 is in that company?Answer: D. 7%. $5,000 + $2,000 = $7,000, which is 7% of $100,000. Not A: adding the two weights ignores how much money sits in each fund.3. Priya holds a broad S&P 500 fund and adds a technology fund. What happens to her technology share?Answer: B. It rises, because the new fund adds more of her largest sector. a technology fund is nearly all technology, so it adds to the largest sector she already had. Not A: more funds only spreads money when they hold different things.
Takeaways
- Your real exposure is your dollars in each company across all your funds, plus any shares you hold directly.
- A second or third fund can add concentration instead of spread.
- Run your funds through My Portfolio X-ray on ETFIQ to see what you own underneath.