MBB vs MUB: Performance, Holdings, Fees & Risk
MBB and MUB are ETFs, but they can differ materially in exposure, yield, fees and risk. MBB is iShares MBS ETF, while MUB is iShares National Muni Bond ETF. MBB is broader by holdings count, with 11,209 positions versus 7,053 for MUB. MBB is more concentrated at the top, based on top-10 holdings weight. Current AlgovestIQ evidence has MBB ahead on AIQ Score, 61 versus 60.
What is the main difference between MBB and MUB?
MBB and MUB have little in common: 0% of their weight is in the same securities.
| Metric | MBB | MUB |
|---|---|---|
| Fund | ||
| Expense ratio | 0.04% | 0.05% |
| Holdings | 11,209 | 7,053 |
| Top-10 concentration | 5.8% | 1.3% |
| Distribution yieldTrailing 12 months | 4.5% | 3.34% |
| Average volume | 3,855,988 | 8,700,223 |
| Performance | ||
| 1Y return | -5.6% | -4.7% |
| YTD return | -5% | -4.4% |
| 5Y annualized returnTotal return, distributions reinvested | -0.1% | +0.3% |
| Risk | ||
| Annualized volatility | 5.1% | 3.7% |
| Max drawdown (1Y) | -8.1% | -7.9% |
| Max drawdown (5Y)Total return, distributions reinvested | -16.8% | -11.6% |
| Beta | 0.16 | 0.10 |
| Sharpe ratio | -1.90 | -2.35 |
| Sortino ratio | -2.68 | -3.02 |
| AlgovestIQ | ||
| AIQ Score | 61/100 | 60/100 |
| AIQ Edge Score | 8/10 | 8/10 |
| Momentum | 55/100 | 57/100 |
| Risk Resilience | 87/100 | 88/100 |
AlgovestIQ AIQ Comparison
iShares MBS ETF vs iShares National Muni Bond ETF
MBB leads
MBB leads by 1 AIQ points, primarily on Value.
Fragile: 1 of 4 evidence groups support MBB, and its current signal state is conflicted.
iShares MBS ETF
iShares National Muni Bond ETF
The Algovestiq AIQ Score currently favors MBB over MUB, 61 versus 60 as of Oct 21, 2026. MBB's advantage is driven primarily by stronger value, while MUB holds the stronger quality profile. MBB also shows the weaker technical structure relative to its 50-day moving average. 1 of 4 covered evidence groups favor MBB today, and the comparison is rated Fragile on stability: the AIQ gap is narrow at 1 points. MBB lead: Stable — the AIQ differential has held near 1 points over 30 sessions.
Compare iShares MBS ETF and iShares National Muni Bond ETF across performance, expense ratio, dividend yield, drawdown, volatility and the Algovestiq AIQ Score.
MBB vs MUB: which fits what
Each row is settled by a single measure. Where the gap is too small to matter it reads Similar, and no row decides the comparison as a whole.
| If you want | MBB | MUB | Fits |
|---|---|---|---|
| Lower costExpense ratio | 0.04% | 0.05% | Similar |
| Broader diversificationNumber of holdings | 11,209 | 7,053 | MBB |
| Lower concentrationWeight of the 10 largest holdings | 5.8% | 1.3% | MUB |
| Higher incomeTrailing 12-month distribution yield | 4.5% | 3.34% | MBB |
| Smaller drawdownsMax drawdown, 5 years | -16.8% | -11.6% | MUB |
| Lower volatilityAnnualized volatility, 1 year | 5.1% | 3.7% | MUB |
Similar means the gap is within 0.01 percentage points of expense ratio, 25% more holdings, 3 points of top-10 weight, 0.2 points of yield, 2 points of drawdown or 1 point of volatility. Past drawdowns and volatility describe the funds’ history, not their future.
Performance over time
Total return with distributions reinvested, from daily closes for both ETFs.
Total return comparison
Growth of $10,000, distributions reinvested
Split-adjusted closes; each distribution is reinvested at the close on its ex-dividend date. Taxes and trading costs are not modeled.
Compare MBB and MUB against another ticker
Open a multi-ticker workspace without changing this focused pair page.
AIQ Factor Divergence
Where the two separate, on the four dimensions behind the AIQ Score. Bars read outward from a shared zero: further from the centre is a wider gap.
- Value45 vs 36MBB +9
- Quality68 vs 72MUB +4
- Momentum55 vs 57Even
- Risk Resilience87 vs 88Even
1 of 4 evidence groups favor MBB. MBB’s edge is concentrated in value; MUB keeps a meaningful quality edge.
What changed since the last close
Latest scored session 2026-10-20, compared against the prior scored session 2026-10-19.
Largest factor move: Momentum +2
No signal started or stopped since the prior session; its 6 active signals are unchanged.
Largest factor move: Momentum -2, not enough on its own to move the overall score.
No signal started or stopped since the prior session; its 6 active signals are unchanged.
MBB's lead widened by 1 AIQ point in the latest session.
Deeper signal detail for each name lives on its own signals page — MBB and MUB both carry a full feed there.
The central trade-off
MBB (iShares MBS ETF): the stronger current systematic profile, led by value.
MUB (iShares National Muni Bond ETF): the counter-case, on quality.
Fund facts, side by side
Two funds tracking overlapping universes are separated by cost and risk far more than by holdings. Those lead here.
| Measure | MBB | MUB | Why it matters |
|---|---|---|---|
| Expense ratio | 0.04% | 0.05% | Lower is better — it compounds against you every year you hold. |
| Holdings | 11,209 | 7,053 | More holdings means broader diversification, not better returns. |
| Average volume | 3,855,988 | 8,700,223 | Liquidity — matters most if you trade size. |
| Annualized volatility | 5.1% | 3.7% | Lower is a steadier ride for the same exposure. |
| Max drawdown (1Y) | -8.1% | -7.9% | The worst peak-to-trough loss over the past year. |
| Sharpe ratio | -1.90 | -2.35 | Return per unit of risk. Higher is better. |
| Beta | 0.16 | 0.10 | Sensitivity to the broad market. Neither direction is better — it depends on the role in your portfolio. |
Where the exposure actually sits
Sector exposure for each fund, ordered by the size of the difference.
How much of the same holdings they own
MBB and MUB share 0% of their weighted exposure across 0 common holdings.
11,154 holdings are unique to MBB, and 7,050 holdings are unique to MUB. Owning both is genuinely additive — most of the capital sits in different securities.
MBB is the more concentrated of the two: its ten largest positions are 5.82% of the fund, against 1.34% for MUB (11,209 holdings vs 7,053). Concentration cuts both ways — it is what drives outperformance when the top names work, and what makes the drawdown deeper when they do not.
What MBB adds that MUB doesn’t
| Holding | MBB | MUB |
|---|---|---|
| FHLMC 30YR UMBS SUPER 2.00% 05/01/2051 | 0.87% | Not held |
| UMBS 30YR TBA(REG A) 5.50% 10/13/2026 | 0.79% | Not held |
| UMBS 30YR TBA(REG A) 5.00% 10/13/2026 | 0.67% | Not held |
| GNMA2 30YR TBA(REG C) 5.50% 09/21/2026 | 0.63% | Not held |
| GNMA2 30YR TBA(REG C) 6.00% 09/21/2026 | 0.56% | Not held |
| GNMA2 30YR TBA(REG C) 5.00% 09/21/2026 | 0.49% | Not held |
What MUB adds that MBB doesn’t
| Holding | MUB | MBB |
|---|---|---|
| UNIVERSITY TEX UNIV REVS 5.00% 08/15/2036 | 0.18% | Not held |
| SAN ANTONIO TEX WTR REV 05/01/2055 | 0.15% | Not held |
| NEW YORK ST TWY AUTH ST PERS I 5.00% 03/15/2048 | 0.15% | Not held |
| NEW JERSEY ST 5.00% 06/01/2028 | 0.12% | Not held |
| HOUSTON TEX HIGHER ED FIN CORP 5.00% 05/15/2034 | 0.12% | Not held |
| NEW YORK ST DORM AUTH ST PERS 4.00% 02/15/2047 | 0.12% | Not held |
Each list is a fund’s largest positions by weight that the other fund does not hold, or holds at less than half the weight.
AIQ Agreement Matrix
1 of 4 covered evidence groups favor MBB. A wide gap backed by one group is a weaker case than a narrow gap backed by five.
| Evidence group | Favors | Reading |
|---|---|---|
| AIQ Score | Even | 61 vs 60 |
| Fundamentals | Not covered | Not covered |
| Valuation | MBB | Value 45 vs 36 |
| Technicals | Even | Price vs 50-day -1% vs -0.8%; vs 200-day -3.7% vs -3.5% |
| Risk Resilience | Even | Risk Resilience 87 vs 88 |
| Analyst expectations | Not covered | Not covered |
✓ agrees with the overall verdict · ✕ points the other way. Groups marked “not covered” lack data on one or both of MBB and MUB and are excluded from the count.
AIQ Decision Stability
The conclusion is sensitive to small changes. Treat the lead as provisional and watch the flip conditions below.
- The AIQ gap is narrow at 1 points. (argues the conclusion is provisional)
- Only 1 of 4 covered evidence groups agree. (argues the conclusion is provisional)
- The lead has been steady session to session. (supports the conclusion holding)
- The leader is throwing conflicting signals. (argues the conclusion is provisional)
Stability combines the score gap, how broadly the evidence agrees, how steady the lead has been across daily snapshots, the current signal state on both names, and analyst dispersion on MBB.
How the comparison changed
120 daily snapshots · Jun 21 – Oct 20MBB lead: Stable — the AIQ differential has held near 1 points over 30 sessions.
- Today
- MBB +1
- 61 vs 60
- 7 sessions ago
- MUB +1
- 58 vs 59
- 30 sessions ago
- MBB +1
- 53 vs 52
- 90 sessions ago
- MBB +2
- 55 vs 53
The lead changed hands 4 times in this window, most recently on Oct 15 when MUB moved ahead of MBB.
AIQ Signal Divergence
Only the signals that bear on the head-to-head. A conflicted name is carrying bullish and bearish rules at the same time — the technical evidence is not pointing one way.
MBB and MUB carry the same 6 signals, so the signals do not separate them: Bollinger Band Squeeze, Death Cross Active, ATR Contraction - Coiling, 52-Week Low Proximity, Downtrend Structure Active, MACD Bullish Crossover.
MBB leads the comparison while carrying a conflicted signal state, which is one reason the stability rating is not higher.
Price vs model alignment
Whether the latest session's price move confirms what the model did over the same session, or contradicts it.
Neither the price nor the AIQ Score moved enough in the latest session to confirm or contradict the other (price +0.06%, AIQ +1 points).
Neither the price nor the AIQ Score moved enough in the latest session to confirm or contradict the other (price +0.1%, AIQ 0 points).
What would flip this result
A state, not a forecast. These are the specific, observable changes that would reverse the verdict — not a price prediction.
- 1MUB closes the Value gap — currently 9 points behind, the largest single contributor to MBB's edge.
- 2MUB's Death Cross Active resolves — a bearish trend rule currently active against it.
- 3MBB's conflicting signal state resolves bearish — it currently carries 1 bullish and 3 bearish rules at once.
- 4A regime shift changes factor weighting — Quality and Value carry the heaviest weights in the composite, so a rotation toward either would move the result most.
The full evidence
Every number behind the verdict. The leader is called above each group so you are not left to solve it from the table.
Performance
MUB leads 4 of 6 windows| Metric | MBB | MUB |
|---|---|---|
| 1 week (5 sessions) | 0.6% | 0.6% |
| 1 month (20 sessions) | -1% | -0.4% |
| 3 months (63 sessions) | -2.9% | -3.3% |
| 6 months (126 sessions) | -4.8% | -4.6% |
| Year to date | -5% | -4.4% |
| 1 year (252 sessions) | -5.6% | -4.7% |
Technicals
Split| Metric | MBB | MUB |
|---|---|---|
| RSI (14) | 64.7 | 66.8 |
| ADX (14) | 34.6 | 31.7 |
| Price vs 50-day | -1% | -0.8% |
| Price vs 200-day | -3.7% | -3.5% |
| Volatility (1M, annualized) | 7% | 6.9% |
Risk
Split| Metric | MBB | MUB |
|---|---|---|
| Beta | 0.16 | 0.1 |
| Sharpe ratio | -1.9 | -2.35 |
| Sortino ratio | -2.68 | -3.02 |
| Max drawdown | -8.1% | -7.9% |
| Current drawdown | -6.6% | -6% |
| Annualized volatility | 5.1% | 3.7% |
| Value at risk (95%) | -0.5% | -0.5% |
Straight answers
Short answers to the questions fund investors ask about this pair, from the figures above.
What is the difference between MBB and MUB?
MBB and MUB have little in common: 0% of their weight is in the same securities.
How much do MBB and MUB overlap?
MBB and MUB share 0% of their weighted exposure across 0 common holdings. 11,154 holdings are unique to MBB, and 7,050 holdings are unique to MUB. Owning both is genuinely additive — most of the capital sits in different securities.
Which ETF is more diversified, MBB or MUB?
MBB holds more positions: 11,209 versus 7,053 for MUB.
Which has the lower expense ratio?
The two are within a basis point: 0.04% for MBB and 0.05% for MUB.
Which ETF has the higher distribution yield?
MBB, with a trailing 12-month distribution yield of 4.5% against 3.34% for MUB.
Which ETF has been more volatile?
MBB has been more volatile over the past year, at 5.1% annualized against 3.7% for MUB.
Which ETF has had the smaller drawdown?
MUB fell less from peak to trough over the past five years: -11.6% against -16.8% for MBB.
Compare MBB and MUB with others
Continue your research
This page answers which of the two. These answer the questions on either side of it.
How this comparison is scored
The Algovestiq AIQ Score composites four factors — Quality, Value, Momentum and Risk, each carrying a fixed weight. Sentiment is reported separately as SentimentPulse and is not folded into the composite. Scores refresh every trading day, and this page regenerates from the latest snapshot rather than being written once.
The verdict names a leader, states how broadly six independent evidence groups agree, and rates how durable that conclusion is given the score gap, its recent trajectory and the current signal state on both names.
How to use side-by-side comparison →This comparison is informational and educational, not investment advice. AIQ scores update daily; re-check after earnings, guidance or macro data that materially changes either name’s factor profile.