You have $200 ready to invest. Two ETFs track the same index and charge the same annual fee. One reports a slightly higher one-year return. Is that enough to choose? Would buying both spread the risk?
For this exercise, you have already chosen a long-term US large-company stock allocation. This $200 is separate from near-term bills and the rest of your portfolio. You measure results in USD and may add $200 a month.
Your goal is a decision you can defend, including a reason to wait.
1. Start with the job and date
These factsheet extracts report the same date: June 30, 2026.
| Reported field | VOO | IVV |
|---|---|---|
| Index | S&P 500 | S&P 500 (USD) |
| Annual expenses | 0.03% | 0.03% |
| ETF net assets ($ millions) | 978,960 | 888,128.94 |
| NAV total return, 1 year | 22.28% | 22.29% |
| Index total return, 1 year | 22.32% | 22.32% |
Returns cover the year ending June 30, 2026, in USD, with distributions reinvested. Fund returns are after operating expenses and before investor tax.
Not supplied: current quotes, broker permissions, transaction charges, full holdings or your other accounts.
Sources: June 2026 factsheets, page 1—Vanguard S&P 500 ETF (F0968_062026, Quick facts; Performance history) and iShares Core S&P 500 ETF (Key Facts; Fees; Annualized Performance). The links may open newer editions.
Check the fund structure, then the index it follows. For an active fund, read its investment mandate instead. The prospectus sets out the objective, strategy, risks and costs. Compare funds doing the job you need done.
A fund targeting a daily multiple does not supply the plain long-term index exposure in this exercise. For an optional all-in-one route, target-date funds package a changing stock/bond mix.
2. Read the exposure
Check how investments are selected, then the largest company, sector and country weights in dated holdings. For international exposure, compare the currency-hedging policy with the currency you plan to spend. A listing currency or exchange address is not a map of the investments.
The extracts cannot show exact overlap with everything you own. That needs complete holdings from the same date, including your other accounts. Where companies earn their revenue is a separate question for company disclosures, which may leave gaps.
Count companies carefully: two share classes can belong to one business. Group them before comparing company concentration.
3. Separate fees from tracking
The disclosed annual expense ratios tie. On a flat $200 balance held for one year, operating expenses come to about $200 × 0.03% = $0.06, before trading costs.
Use tracking difference, the fund's NAV total return minus its matching index return:
- VOO: 22.28% − 22.32% = −0.04 percentage points.
- IVV: 22.29% − 22.32% = −0.03 percentage points.
The reported gap is 0.01 percentage points: $0.02 on a $200 starting investment over that year. Small trading differences and rounding can affect that gap. Two cents in one year cannot establish a lasting winner.
These return gaps already reflect expenses; they are not the bid-ask spread. Close tracking follows an index down as well as up.
4. Check the trade
Assets under management (AUM) here means net assets in the fund or ETF share class being compared. VOO's figure excludes the fund's non-ETF share classes. Size and history give context, but cannot guarantee an easy trade.
Check the bid and ask and liquidity in the underlying investments; past trading volume alone is not enough. Review the issuer's historical spreads and premiums or discounts—market prices above or below per-share NAV. Match timestamps: comparing a live price with yesterday's NAV cannot establish overpricing.
For this $200 purchase, check these missing facts:
- Access: Whether your account can buy each ETF; using USD does not establish eligibility.
- Quantity: Whether you can buy fractions of shares or make recurring dollar purchases.
- Cost: Current share prices and spreads, commissions and currency-conversion charges.
Get prices from a current quote and permissions and charges from your broker. An old factsheet is not an order preview.
5. Count the companies
Holdings overlap means funds own some of the same investments. Look-through exposure adds up your stake in an underlying company across funds and any shares you own directly.
Return to Market Basket and Digital Future: their weights in Tessel, our fictional software company, are still 4% and 40%. This time, compare holding one fund with combining them in a $10,000 portfolio:
- Market Basket only: $10,000 × 4% = $400 in Tessel.
- Two funds: $8,000 in Market Basket plus $2,000 in Digital Future puts $320 + $800 = $1,120 in Tessel.
The total stays the same, yet the Tessel slice nearly triples. This 80/20 split is an exposure exercise, not an allocation recommendation.
Multiply each fund's share of your portfolio by the company's weight inside it, then add any direct holding's portfolio weight. With no direct Tessel shares:
This measures your Tessel exposure; the funds' complete overlap still needs every holding.
6. Make the call
One defensible decision note:
For this $200 job, either ETF supplies US large-company exposure at a reported 0.03% annual cost. Both track the S&P 500, so buying both adds no new market. Overlap with my other accounts is unknown. I will wait to order until I check access, purchase-size permissions and actual trade costs.
Both make the provisional shortlist. Suitable dollar-purchase terms for only one, or a meaningful known trading-cost advantage, could break the tie. If the job were bonds or stocks outside the US, neither would fit. Waiting has a purpose when you can name the missing fact.
Once the checks pass, follow your first purchase from order to holding, then write a simple plan and review rules. A simple fund plan is a complete investing route.
In short
- Compare funds doing the same job, using the same dates.
- Annual expenses, trading costs, price/NAV gaps and tracking differences answer different questions.
- A second fund can increase your stake in companies you already own.
- A factsheet can support a shortlist without being enough to place an order.
- A useful decision names what would change it.