SPYM vs VTWNX: 18% overlap
State Street SPDR Portfolio S&P 500 ETF and Vanguard Target Retirement 2020 share 18.0% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
Different holding dates. These holdings were published about 4 months apart — VTWNX as of 2026-03-31, the rest through 2026-07-23. Each fund is compared using its most recent file, so any trading in between shows up as a difference.
You would hold two tickers and get the diversification of 1.8. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
SPYM and VTWNX hold 502 of the same securities. The ten contributing most to the overlap figure:
| Holding | in SPYM | in VTWNX | Δ |
|---|---|---|---|
| NVDA | 7.9% | 1.3% | 6.7% |
| AAPL | 7.4% | 1.2% | 6.2% |
| MSFT | 4.4% | 0.8% | 3.7% |
| AMZN | 3.6% | 0.6% | 3.0% |
| GOOGL | 2.9% | 0.6% | 2.3% |
| AVGO | 2.9% | 0.5% | 2.4% |
| GOOG | 2.4% | 0.5% | 1.9% |
| MU | 1.8% | 0.4% | 1.4% |
| META | 2.1% | 0.3% | 1.7% |
| TSLA | 1.4% | 0.3% | 1.1% |
Where SPYM and VTWNX differ
Sector weights as a share of each fund, ordered by the size of the gap rather than the size of the sector — two funds that overlap heavily still usually diverge somewhere.
| Sector | SPYM | VTWNX | Δ |
|---|---|---|---|
| Unclassified | 0.0% | 29.8% | −29.8pp |
| Information Technology | 37.5% | 10.0% | +27.5pp |
| Treasuries | 0.0% | 17.1% | −17.1pp |
| MBS Pass-Through | 0.0% | 7.2% | −7.2pp |
| Communication Services | 9.3% | 2.3% | +7.0pp |
| Health Care | 9.1% | 2.7% | +6.5pp |
| Consumer Discretionary | 8.7% | 2.9% | +5.8pp |
| Corporate — industrial & other | 0.0% | 5.5% | −5.5pp |
Δ is SPYM minus VTWNX, in percentage points. Sector data is not published by every issuer, so “Unclassified” is a real category rather than a gap in the table.
What each fund holds alone
0.1% of SPYM by weight, held in no part of VTWNX.
80.2% of VTWNX by weight, held in no part of SPYM.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| SPYM | VTWNX | |
|---|---|---|
| Top 10 holdings | 36.9% | 44.9% |
| Positions held | 507 | 7 |
| Cost per $10,000 held, per year | $2 | $8 |
Cost is the expense ratio applied to $10,000; it excludes any brokerage commission, bid-ask spread or tax consequence. Figures are facts about the funds, not a suggestion about which to hold.
Frequently asked
How much do SPYM and VTWNX overlap?
SPYM and VTWNX overlap 18.0% by portfolio weight — moderate overlap. They share 502 holdings. The figure comes from current issuer holdings files (SPYM as of 2026-07-23, VTWNX as of 2026-03-31).
How is the overlap between SPYM and VTWNX calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If SPYM holds a stock at 6% and VTWNX holds the same stock at 4%, 4% counts as shared. The result is bounded between 0% and 100%, and it is computed after looking through any fund-of-funds to the underlying holdings.
Is it redundant to hold both SPYM and VTWNX?
That depends on your goals — we state facts, not advice. At 18.0% overlap, each fund still contributes meaningfully distinct exposure.
What does SPYM own that VTWNX doesn't?
SPYM holds 507 positions and VTWNX holds 7; 4 of SPYM's positions don't appear in VTWNX at all, and they are 0.1% of SPYM by weight.
You probably hold more than two funds
This page compares SPYM and VTWNX. Paste your whole portfolio — brokerage, 401(k), IRA — and see the overlap across every fund at once, plus what you actually own underneath them and your own Effective Funds number. Free, no account, nothing stored.
X-ray my portfolio — free →Watch SPYM vs VTWNX
We re-read both funds’ published holdings every weeknight. Leave an address and we'll tell you when what's inside actually changes.
Not sending yet — email alerts are built but switched off, and you'll be among the first when they turn on. No spam, one-click unsubscribe.
Related comparisons
Sources: issuer holdings files, SPYM as of 2026-07-23, VTWNX as of 2026-03-31. Weights are fractions of each fund. Diagnostics, not advice.