Data as of Sep 12, 2026. Both funds on the fields they both publish, from the same sources.
MBB vs MGK: how they differ
MBB and MGK hold 0% of their weight in the same names, and MGK returned more over the year.
iShares MBS ETF and Vanguard Mega Cap Growth Index Fund.
What they hold in common
By the books each fund has filed, MBB and MGK hold 0% of their money in the same securities at the same weight.
| Only in MBB | Only in MGK |
|---|---|
| Freddie Mac 1.07% | NVIDIA Corp 13.29% |
| Government National Mortgage Association 0.97% | Apple Inc 12.19% |
| UMBS, TBA 0.85% | Microsoft Corp 7.52% |
| Government National Mortgage Association 0.69% | Alphabet Inc 5.93% |
| UMBS, TBA 0.66% | Alphabet Inc 4.67% |
| Government National Mortgage Association 0.56% | Amazon.com Inc 4.47% |
| Government National Mortgage Association 0.55% | Broadcom Inc 4.28% |
| Government National Mortgage Association 0.54% | Meta Platforms Inc 4.08% |
Weight overlap is an ETFIQ calculation: for every security both funds hold, the smaller of the two weights, summed. Above 50%, holding both is close to holding one of them twice. Holdings dated Jun 30, 2026 and May 31, 2026.
| MBB iShares MBS ETF | MGK Vanguard Mega Cap Growth Index Fund | |
|---|---|---|
| Where it sits | Core index fund | Core index fund |
| Issuer | iShares | Vanguard |
| What it is | Mbs | Mega Cap Growth |
| Total return, 1 year | −0.1% | +14.9% |
| S&P 500 over the same days | +17.5% | +17.5% |
| Gap to the S&P 500 | −17.6 pts | −2.6 pts |
| Expense ratio | 0.04% | 0.07% |
| Holdings | 11144 | 56 |
MBB in plain words
MBB is a bond fund tracking the Mbs. Over the year to Sep 11, 2026 it returned −0.1% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.04% a year. It sat 3.3% below its high of Feb 27, 2026 on Sep 11, 2026.
MGK in plain words
MGK is an index equity fund tracking the Mega Cap Growth. Over the year to Sep 11, 2026 it returned +14.9% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.07% a year. By its holdings filed for Jun 30, 2026, 99% of the fund by weight is stocks the S&P 500 also holds, across 56 positions, with the top ten at 63.8%.
Questions people ask
- Which returned more over the last year, MBB or MGK?
- In the year to Sep 12, 2026, with distributions reinvested, MBB returned −0.1% and MGK returned +14.9%, so MGK returned more. One year is one year; the longer windows are in the table.
- Which is cheaper, MBB or MGK?
- MBB charges 0.04% a year and MGK charges 0.07%, so MBB is cheaper. Fees come from each fund's prospectus.
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Where these figures came from
ETFIQ links to the documents behind every figure. It is not affiliated with any issuer, and a link is not an endorsement.
Cite this page. ETFIQ, MBB against MGK, data as of Sep 12, 2026. https://etfiq.com/compare/any/MBB-MGK Free to use with attribution; the underlying files are at Open data.
A comparison is not a recommendation. Standards and sources