AGG vs IUSB: Holdings Overlap
AGGiShares Core U.S. Aggregate Bond ETF
iShares · 13266 holdings · $137.7B · as of 2026-05-31
IUSBiShares Core Universal USD Bond ETF
iShares · 17783 holdings · $43.2B · as of 2026-04-30
Holdings snapshots are 31 days apart (AGG: 2026-05-31, IUSB: 2026-04-30). Weights and index membership change between snapshots, so the true current overlap is typically higher than shown. For funds tracking the same index, the gap can be 5–15 points.
How similar are AGG and IUSB?
iShares Core U.S. Aggregate Bond ETF (AGG, by iShares) holds 13266 positions; iShares Core Universal USD Bond ETF (IUSB, by iShares) holds 17783. They have 11355 holdings in common, and by portfolio weight the two funds are 70.3% identical. In practical terms the pair is heavily overlapping, with largely the same stocks driving both funds.
- Overlap by Weight
- 70.3%Sum of the smaller weight of each shared holding
- Shared Holdings
- 11355AGG holds 13266 · IUSB holds 17783
- Weight in Shared Holdings
- AGG 90%·IUSB 79%Share of each fund's weight in stocks both funds own
Based on each fund's latest official holdings. How is this calculated?
What makes each fund different
Only in AGG
1911 of 13266 positions (8.2% of the fund) are not held by IUSB. Showing the top 30 by weight.
- Uniform Mortgage-Backed Security, TBA0.20%
- Uniform Mortgage-Backed Security, TBA0.16%
- Ginnie Mae0.14%
- Uniform Mortgage-Backed Security, TBA0.14%
- Uniform Mortgage-Backed Security, TBA0.13%
- Ginnie Mae0.12%
Only in IUSB
6428 of 17783 positions (20.0% of the fund) are not held by AGG. Showing the top 30 by weight.
- U.S. Treasury Notes0.26%
- U.S. Treasury Notes0.24%
- Uniform Mortgage-Backed Securities0.22%
- Government National Mortgage Association0.21%
- Uniform Mortgage-Backed Securities0.20%
- U.S. Treasury Notes0.19%
Performance
| Fund | 1M | YTD | 1Y | 3Y (ann.) | 5Y (ann.) | 10Y (ann.) | Yield |
|---|---|---|---|---|---|---|---|
| AGG | -0.3% | +0.0% | +2.4% | +4.2% | -0.2% | +1.4% | 4.04% |
| IUSB | -0.2% | +0.3% | +2.8% | +4.7% | +0.2% | +1.8% | 4.28% |
Total returns including dividends, from adjusted daily closes as of 2026-08-07. 3Y/5Y/10Y are annualized. Yield is trailing-12-month distributions over the last close. Past performance does not predict future results.
Project the growth of $10,000 in AGG vs IUSB →
Shared Holdings(11355)
The top 10 shared positions account for 5% of the overlap, led by U.S. Treasury Notes, U.S. Treasury Notes and U.S. Treasury Notes.
| U.S. Treasury Notes | 0.41% | 0.37% | 0.37% |
|---|---|---|---|
| U.S. Treasury Notes | 0.38% | 0.37% | 0.37% |
| U.S. Treasury Notes | 0.41% | 0.37% | 0.37% |
| U.S. Treasury Notes | 0.40% | 0.37% | 0.37% |
| U.S. Treasury Notes | 0.39% | 0.36% | 0.36% |
| U.S. Treasury Notes | 0.39% | 0.36% | 0.36% |
| U.S. Treasury Notes | 0.42% | 0.36% | 0.36% |
| U.S. Treasury Notes | 0.40% | 0.35% | 0.35% |
| U.S. Treasury Notes | 0.39% | 0.34% | 0.34% |
| U.S. Treasury Notes | 0.39% | 0.33% | 0.33% |
| U.S. Treasury Notes | 0.35% | 0.33% | 0.33% |
| U.S. Treasury Notes | 0.31% | 0.32% | 0.31% |
| U.S. Treasury Notes | 0.37% | 0.29% | 0.29% |
| U.S. Treasury Notes | 0.29% | 0.33% | 0.29% |
| U.S. Treasury Notes | 0.31% | 0.29% | 0.29% |
| U.S. Treasury Notes | 0.33% | 0.28% | 0.28% |
| U.S. Treasury Notes | 0.28% | 0.34% | 0.28% |
| U.S. Treasury Notes | 0.27% | 0.27% | 0.27% |
| U.S. Treasury Notes | 0.31% | 0.27% | 0.27% |
| U.S. Treasury Notes | 0.26% | 0.28% | 0.26% |
| U.S. Treasury Notes | 0.30% | 0.26% | 0.26% |
| U.S. Treasury Notes | 0.33% | 0.26% | 0.26% |
| U.S. Treasury Notes | 0.32% | 0.26% | 0.26% |
| U.S. Treasury Notes | 0.31% | 0.25% | 0.25% |
| U.S. Treasury Notes | 0.29% | 0.25% | 0.25% |
Showing the top 250 of 11355 shared holdings by overlap weight.
Frequently Asked Questions
How much do AGG and IUSB overlap?
AGG and IUSB overlap by 70.3% of portfolio weight. They share 11355 holdings (AGG holds 13266 positions and IUSB holds 17783), based on each fund's latest SEC-reported holdings.
Is it redundant to own both AGG and IUSB?
The two portfolios are 70.3% identical by weight. Owning both mostly doubles down on the shared core rather than diversifying: the same large positions drive both funds.
What are the biggest shared holdings of AGG and IUSB?
The largest positions held by both funds are U.S. Treasury Notes, U.S. Treasury Notes, U.S. Treasury Notes, U.S. Treasury Notes and U.S. Treasury Notes. Together the top 10 shared positions account for 5% of the total overlap.
What does AGG own that IUSB doesn't?
1911 positions (8.2% of AGG) are unique to AGG, led by Uniform Mortgage-Backed Security, TBA, Uniform Mortgage-Backed Security, TBA and Ginnie Mae. In the other direction, 6428 positions (20.0% of IUSB) are unique to IUSB.