AGG vs IUSB

AGGAiShares Core U.S. Aggregate Bond ETF

IUSBAiShares Core Universal USD Bond ETF

In short

AGG Launched in 2003, one of the first funds to pack the entire U.S. investment-grade bond market into a single ticker: Treasuries, corporates and mortgage bonds, three basis points a year, cash paid monthly.

IUSB Most core bond funds stop at investment grade. IUSB keeps going, folding high-yield USD debt into the same wrapper across roughly 18,000 bonds, for 0.06% a year.

Stated mandate

AGG The fund seeks to track the Bloomberg U.S. Aggregate Bond Index, providing broad exposure to the total U.S. investment-grade bond market.

IUSB The Fund seeks to track an index of U.S.-dollar-denominated bonds spanning investment-grade and high-yield sectors.

Why people hold it

• AGG 0.03% a year against a peer-group median near 0.36%. On a bond fund, the fee comes straight out of the coupon, so the gap matters more than it looks.
• A $100 billion-plus fund and very actively traded, the kind of depth that keeps bid-ask costs down for retail-sized orders.
• Tracks the Bloomberg U.S. Aggregate closely, with one of the tightest index-following records in its peer group. Income is distributed monthly.
• Running since 2003, giving it one of the longest track records among U.S. bond index ETFs.

• IUSB 0.06% a year, a fraction of what the typical broad bond fund in its category charges, and iShares has run it since 2014.
• Roughly 18,000 bonds spanning investment-grade and high-yield sectors, so one ticker covers ground a plain Agg tracker leaves on the table.ishares.com
• Tracks its index closely, trades heavily, and sits on a multi-billion-dollar asset base. Income is paid monthly.
• Among the strongest implementations in a crowded field of nearly 200 core bond funds.

Worth knowing

• AGG Investment grade and U.S. dollar only. High-yield debt and foreign bonds sit outside the mandate, so this is designed as core ballast rather than a yield hunt.
• Rate risk comes as it comes. The index gets tracked whether yields rise or fall, with no manager stepping in to shorten duration.
• The same index is sold by SPAB, SCHZ and BBAG at the same 0.03%. The portfolio is the commodity here; scale and trading depth are the tiebreakers.

• IUSB That high-yield sleeve is the trade-off: more credit risk than an investment-grade-only fund, and more movement when spreads widen.
• BND, SPAB and SCHZ charge 0.03%, half IUSB's fee, but they stay inside investment grade.
• Payouts land monthly, but the amount floats with the coupons underneath. Nothing about the income stream is fixed.

Full AGG profile⁠

Full IUSB profile⁠