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ETF Nasdaq USD

iShares MBS ETF MBB

Issuer: iShares SEC registrant: iShares Trust Fixed income · US
Watch MBB (sign in) Add to portfolio (MBB) Set an alert for MBB Compare MBB with other ETFs Position size calculator for MBB at 90.49 USD

How position sizing works
Last price 90.49 USD Change: Up +0.27 Percent change: Up +0.30%

Source: Yahoo Finance (opens in a new tab) Observed · 1 day ago Quotes may be delayed

Net expense ratio
0.04%
Prospectus 29 Jun 2026
Net assets
$38.7B
As of 31 May 2026
Holdings
11,146
As of 31 May 2026
12-month distribution yield
4.50%
Monthly
Asset class
Fixed income
From holdings

iShares MBS ETF (MBB) is an exchange-traded fund listed on the Nasdaq in the United States, issued by iShares. Its category is Fixed income · US (fixed income). Its last price was US$90.49 on 20 Oct 2026. Its net expense ratio is 0.04% a year, from its prospectus dated 29 Jun 2026. It reported net assets of US$38.74 billion as of 31 May 2026. Its latest holdings report lists 11,146 holdings as of 31 May 2026. Over the last 12 months it paid distributions of US$4.07 a unit, a 12-month distribution yield of 4.50%, paid monthly.

General information only: nothing on TakeProfits takes into account your objectives, financial situation or needs, and it isn't personal financial advice or a recommendation to buy or sell anything. Consider whether it suits you and get advice from a licensed adviser before acting. Market data may be delayed and comes from third-party sources.

Fees

Total annual operating expenses (gross)
0.04%
Net, after fee waivers or reimbursements
0.04%
Management fee
0.04%
Prospectus date
29 Jun 2026
Filed with the SEC
18 Jun 2026

Source: SEC prospectus risk/return data sets (opens in a new tab) Filed

Size and reporting

Net assets
$38,738,470,076
Total assets
$40,895,386,832
Holdings as of
31 May 2026
Report made public
24 Jul 2026 (54 days after the month end)

Net assets are for the whole fund series, which for some funds (Vanguard's, for example) also includes mutual fund share classes.

Source: SEC Form N-PORT (opens in a new tab) Filed

Top holdings

Largest 25 of 11,146 positions, as of 31 May 2026. Weight is the percent of net assets the fund reported.

MBB top holdings as of 31 May 2026
# Holding Identifier Weight Value (USD) Type Country Currency
1 BLACKROCK CASH FUNDS BlackRock Cash Funds: Treasury, SL Agency Shares US0669224778 6.77% $2.6B Short-term investment vehicles (cash funds) United States USD
2 Freddie Mac Freddie Mac Pool US3132DWBP77 1.05% $405.6M Mortgage-backed securities United States USD
3 Government National Mortgage Association Ginnie Mae US21H0526606 0.95% $367.1M Mortgage-backed securities United States USD
4 UMBS, TBA Uniform Mortgage-Backed Security, TBA US01F0526644 0.83% $322.2M Mortgage-backed securities United States USD
5 Government National Mortgage Association Ginnie Mae US21H0506640 0.67% $260.2M Mortgage-backed securities United States USD
6 UMBS, TBA Uniform Mortgage-Backed Security, TBA US01F0506687 0.64% $249.2M Mortgage-backed securities United States USD
7 Government National Mortgage Association Ginnie Mae II Pool US3618N5A332 0.55% $213.0M Mortgage-backed securities United States USD
8 Government National Mortgage Association Ginnie Mae II Pool US36179WP937 0.54% $209.9M Mortgage-backed securities United States USD
9 Government National Mortgage Association Ginnie Mae II Pool US36179WTX64 0.53% $206.3M Mortgage-backed securities United States USD
10 Fannie Mae Fannie Mae Pool US31418D7E66 0.52% $202.3M Mortgage-backed securities United States USD
11 Freddie Mac Freddie Mac Pool US3132DWBH51 0.50% $194.5M Mortgage-backed securities United States USD
12 Government National Mortgage Association Ginnie Mae US21H0606630 0.46% $176.7M Mortgage-backed securities United States USD
13 Government National Mortgage Association Ginnie Mae II Pool US36179WJR07 0.45% $176.2M Mortgage-backed securities United States USD
14 Fannie Mae Fannie Mae Pool US31418D6B37 0.44% $171.5M Mortgage-backed securities United States USD
15 Fannie Mae Fannie Mae Pool US3140XLE460 0.44% $169.2M Mortgage-backed securities United States USD
16 Government National Mortgage Association Ginnie Mae II Pool US36179YFL39 0.41% $158.9M Mortgage-backed securities United States USD
17 Government National Mortgage Association Ginnie Mae II Pool US36179WY855 0.36% $140.7M Mortgage-backed securities United States USD
18 Government National Mortgage Association Ginnie Mae II Pool US36179WFG87 0.35% $137.2M Mortgage-backed securities United States USD
19 UMBS, TBA Uniform Mortgage-Backed Security, TBA US01F0606677 0.34% $130.5M Mortgage-backed securities United States USD
20 Fannie Mae Fannie Mae Pool US3140XREC56 0.33% $126.7M Mortgage-backed securities United States USD
21 Fannie Mae Fannie Mae Pool US31418DXK35 0.33% $126.6M Mortgage-backed securities United States USD
22 Fannie Mae Fannie Mae Pool US31418D4X74 0.31% $121.3M Mortgage-backed securities United States USD
23 Government National Mortgage Association Ginnie Mae II Pool US36179WVT25 0.31% $120.4M Mortgage-backed securities United States USD
24 Government National Mortgage Association Ginnie Mae II Pool US36179WLP13 0.30% $117.1M Mortgage-backed securities United States USD
25 Fannie Mae Fannie Mae Pool US31418DYB27 0.30% $114.6M Mortgage-backed securities United States USD

The fund reported 11,146 positions; the largest 2,000 are kept and make up 90.4% of its reported weight. Breakdowns below use every position.

Source: SEC Form N-PORT (opens in a new tab) Made public Holdings as of 31 May 2026

All 2,000 stored holdings

Breakdowns

Sums of reported weights over every position in the report. Totals can differ from 100% because of derivatives, borrowing and cash.

Asset type

Asset type by weight
TypeWeightBar
Mortgage-backed securities 98.10%
Short-term investment vehicles (cash funds) 6.77%

Country

Country by weight
CountryWeightBar
United States 104.88%

The country each issuer is assigned to in the report.

Currency exposure

Currency exposure by weight
CurrencyWeightBar
US dollar (USD) 104.88%

The currency each holding is denominated in. Currency hedges are not netted off, so a hedged fund still shows its holdings' currencies.

Sector

No sector data

None of this fund's holdings matched a stock listed on this site, so no sector is shown.

Partial coverage: sectors are known for 0.0% of net assets, the holdings matched by CUSIP or ticker to US stocks listed on this site. The rest is not assigned a sector.

Source: SEC Form N-PORT (opens in a new tab) Holdings as of

Distributions

Paid in the last 12 months
$4.0700
12 payments per unit
12-month yield
4.50%
Distributions only, not total return
Frequency
Monthly
From the gaps between ex-dates
Latest ex-date
1 Oct 2026

12-month yield = distributions per unit with an ex-date in the last 12 months ($4.0700) ÷ latest price ($90.49) × 100 = 4.50%. It looks back, so it is not a forecast; special distributions in the window are included.

Why a distribution yield is not the fund's return: yield vs total return

Distribution history table (57 payments)
MBB distributions per unit by ex-date
Ex-dateAmount per unit
1 Oct 2026$0.3660
1 Sep 2026$0.3390
3 Aug 2026$0.3410
1 Jul 2026$0.3370
1 Jun 2026$0.3330
1 May 2026$0.3350
1 Apr 2026$0.3330
2 Mar 2026$0.3280
2 Feb 2026$0.3350
19 Dec 2025$0.3340
1 Dec 2025$0.3470
3 Nov 2025$0.3420
1 Oct 2025$0.3360
2 Sep 2025$0.3380
1 Aug 2025$0.3320
1 Jul 2025$0.3320
2 Jun 2025$0.3250
1 May 2025$0.3250
1 Apr 2025$0.3310
3 Mar 2025$0.3200
3 Feb 2025$0.3410
18 Dec 2024$0.2940
2 Dec 2024$0.3070
1 Nov 2024$0.3100
1 Oct 2024$0.3110
3 Sep 2024$0.3180
1 Aug 2024$0.3090
1 Jul 2024$0.3050
3 Jun 2024$0.3000
1 May 2024$0.2820
1 Apr 2024$0.2830
1 Mar 2024$0.2920
1 Feb 2024$0.2970
14 Dec 2023$0.2760
1 Dec 2023$0.2800
1 Nov 2023$0.2740
2 Oct 2023$0.2900
1 Sep 2023$0.2640
1 Aug 2023$0.2760
3 Jul 2023$0.2640
1 Jun 2023$0.2690
1 May 2023$0.2600
3 Apr 2023$0.2510
1 Mar 2023$0.2500
1 Feb 2023$0.2430
15 Dec 2022$0.2410
1 Dec 2022$0.2270
1 Nov 2022$0.1960
3 Oct 2022$0.1980
1 Sep 2022$0.1970
1 Aug 2022$0.1840
1 Jul 2022$0.1500
1 Jun 2022$0.1620
2 May 2022$0.1480
1 Apr 2022$0.1360
1 Mar 2022$0.1370
1 Feb 2022$0.1660

Source: Yahoo Finance (opens in a new tab) Checked · 2 days ago Amounts are adjusted for later unit splits

Filings and sources

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IMPORTANT FINANCIAL DISCLAIMER: The information provided on this platform is for educational and informational purposes only and should not be construed as investment advice. All investments involve risk, including potential loss of principal. Past performance does not guarantee future results. Take Profits is not a registered investment advisor and does not provide personalized investment advice. Users should conduct their own research and consult with qualified financial professionals before making investment decisions. Market data may be delayed and is provided by third-party sources.

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