Iron Mountain Incorporated (IRM) vs Simon Property Group, Inc. (SPG)

A side-by-side comparison of Iron Mountain Incorporated and Simon Property Group, Inc. across valuation, profitability, dividends, and growth — built entirely from reported fundamentals, as of September 8, 2026. Differences are shown without an overall score or investment verdict.

Compare

Total returnIRM vs SPG

growth of $100 · dividends reinvested · last 10y
IRM +440.0% (+18.4%/yr)SPG +61.6% (+4.9%/yr)IRM compounded faster over this window
0200400600Start $10020182020202220242026$540$162
IRM SPG

IRM vs SPG: by the numbers

  • SPG is the larger company ($68.01B vs $35.27B market cap).
  • SPG converts more revenue to profit (68.41% vs 5.54% net margin).
  • IRM grew revenue faster over the past five years (11.97% vs 8.17% CAGR).
  • SPG pays the higher dividend yield (4.20% vs 2.89%).

Metrics side by side

Valuation

MetricIRMSPG
P/E ratio83.4714.81
Forward P/E46.8631.51
P/S ratio4.6311.47
P/B ratioN/A17.95
EV / EBITDA22.0821.53
FCF yieldN/A4.08%

For REITs like Iron Mountain Incorporated, GAAP P/E is distorted: heavy non-cash property depreciation depresses reported earnings and overstates the multiple. Real-estate companies are valued on funds from operations (FFO / AFFO) and price-to-FFO — see the Funds From Operations section. The P/E is shown for reference only.

For REITs like Simon Property Group, Inc., GAAP P/E is distorted: heavy non-cash property depreciation depresses reported earnings and overstates the multiple. Real-estate companies are valued on funds from operations (FFO / AFFO) and price-to-FFO — see the Funds From Operations section. The P/E is shown for reference only.

Profitability

MetricIRMSPG
Gross margin25.69%84.11%
Operating margin18.76%48.12%
Net margin5.54%68.41%
ROEN/A107.08%
ROIC6.34%8.81%

Dividends

MetricIRMSPG
Dividend yield2.89%4.20%
Payout ratio241.21%62.23%

Iron Mountain Incorporated's payout ratio is measured against GAAP earnings, which non-cash depreciation depresses for REITs — the dividend is conventionally assessed against funds from operations (FFO / AFFO) instead, so the GAAP figure overstates the payout burden.

Simon Property Group, Inc.'s payout ratio is measured against GAAP earnings, which non-cash depreciation depresses for REITs — the dividend is conventionally assessed against funds from operations (FFO / AFFO) instead, so the GAAP figure overstates the payout burden.

Growth (annualized)

MetricIRMSPG
Revenue CAGR (5Y)11.97%8.17%
EPS CAGR (5Y)-16.26%31.55%
FCF CAGR (5Y)-43.23%1.52%
Total return CAGR (5Y)23.50%15.03%

Frequently asked

Which has grown faster, IRM or SPG?
Over the past five years, IRM grew revenue faster — IRM at a 11.97% CAGR versus SPG at 8.17%.
Does IRM or SPG pay a bigger dividend?
IRM yields 2.89% and SPG yields 4.20% based on trailing dividends and the latest price.
Is IRM or SPG more profitable?
SPG runs the higher net margin — IRM at 5.54% versus SPG at 68.41%.
How have IRM and SPG total returns compared?
Over the past 10 years, IRM delivered 17.88% and SPG delivered 4.86% annualized total return. Past performance doesn't predict future results.

Figures are sourced from reported fundamentals and the latest end-of-day price. This comparison is informational only and is not investment advice. Past performance does not predict future results. See our methodology. Compiled by TGMCharts Research · data verified September 8, 2026.