ETF comparison
IBB vs XBI
Both Healthcare.
iShares Biotechnology ETF · State Street SPDR S&P Biotech ETF
Holdings overlap
125 positions appear in both funds. Buying equal dollars of IBB and XBI would leave roughly 42.0% of each dollar exposed to the same underlying securities.
Side by side
Sub-score comparison
Tracking quality isn't part of the composite — see what we don't score for why.
Cost difference
XBI is 9 bps cheaper than IBB. On a $100,000 position that's about $90/yr more in fees for IBB.
Fee figure is the annual expense charged on $100,000. To see how the gap compounds over a multi-decade holding period, open the cost calculator pre-filled with IBB vs XBI.
Top shared holdings
125 shared in total| # | Holding | In IBB | In XBI | Overlap |
|---|---|---|---|---|
| 1 | Insmed, Inc. | 3.20% | 1.34% | 1.34% |
| 2 | United Therapeutics Corp. | 2.30% | 1.24% | 1.24% |
| 3 | Alnylam Pharmaceuticals, Inc. | 3.99% | 1.18% | 1.18% |
| 4 | Natera, Inc. | 2.41% | 1.16% | 1.16% |
| 5 | Neurocrine Biosciences, Inc. | 1.18% | 1.16% | 1.16% |
| 6 | Regeneron Pharmaceuticals, Inc. | 7.21% | 1.14% | 1.14% |
| 7 | Incyte Corp. | 1.70% | 1.13% | 1.13% |
| 8 | Bridgebio Pharma, Inc. | 1.13% | 1.19% | 1.13% |
| 9 | Ionis Pharmaceuticals, Inc. | 1.11% | 1.14% | 1.11% |
| 10 | Revolution Medicines, Inc. | 1.54% | 1.11% | 1.11% |
| 11 | Biogen, Inc. | 2.46% | 1.10% | 1.10% |
| 12 | Gilead Sciences, Inc. | 7.75% | 1.09% | 1.09% |
Only in IBB
131 total- BlackRock Funds III 9.66%
- Argenx SE 3.07%
- BeOne Medicines Ltd. 1.93%
- Illumina, Inc. 1.68%
- Genmab A/S 1.17%
- Medpace Holdings, Inc. 1.00%
- Ascendis Pharma A/S 0.96%
- Charles River Laboratories International, Inc. 0.77%
- Bio-Techne Corp. 0.74%
- Axsome Therapeutics, Inc. 0.66%
Only in XBI
29 total- TG Therapeutics Inc 1.35%
- Celcuity Inc 1.12%
- AbbVie Inc 1.09%
- Viking Therapeutics Inc 1.04%
- Immunome Inc 0.86%
- Catalyst Pharmaceuticals Inc 0.76%
- Viridian Therapeutics Inc 0.70%
- Soleno Therapeutics Inc 0.67%
- Dianthus Therapeutics Inc 0.66%
- Ardelyx Inc 0.62%
Open IBB or XBI at a brokerage
Both funds trade commission-free at major US brokerages.
Affiliate links — opening an account through these earns PlainIndex a one-time referral. Scoring is computed before any affiliate consideration; see our methodology and funding disclosure.
Holdings overlap is the sum of min(weight_a, weight_b) over positions
matched on ISIN (CUSIP fallback). Methodology: see
/methodology/.
Comparing two funds doesn't endorse swapping one for the other. Tax-lot history, account type, and personal goals matter — PlainIndex publishes data and methodology, not investment advice.