American Tower Corp /ma/ vs Simon Property Group (AMT vs SPG)

Side by side from their SEC filings: revenue, margins, growth, returns and valuation, plus short interest, insider activity and institutional ownership.

American Tower Corp /ma/ is the larger company by revenue ($10.6B vs $6.4B). Simon Property Group carries the larger market value ($83.4B vs $78.5B). Simon Property Group has grown revenue faster over the last 4 fiscal years (+24.4% cumulative vs +13.8%). Simon Property Group runs the higher operating margin (49.9% vs 45.5%). Simon Property Group trades at the lower trailing P/E (15.3x vs 27.2x).

About American Tower Corp /ma/

American Tower Corp is a global real estate investment trust that owns, operates, and develops multitenant communications real estate. The company leases space on its communications sites, including towers and distributed antenna system networks, to wireless service providers, broadcasters, government agencies, and other tenants. It also operates data centers and provides tower-related services such as site application, zoning, permitting, and construction management primarily in the United States.

About Simon Property Group

Simon Property Group Inc. operates as a real estate investment trust specializing in retail real estate. The company owns and manages shopping malls, premium outlet centers, and other retail properties across the United States. It serves retailers and consumers by providing commercial spaces for retail businesses.

Head to head (AMT FY2025 vs SPG FY2025)

Metric	AMTFY2025	SPGFY2025
Revenue	$10.64B	$6.36B
Revenue growth (YoY)	5.1%	6.7%
Gross margin	—	—
Operating margin	45.5%	49.9%
Net margin	24.7%	84.3%
Net income	$2.63B	$5.36B
Diluted EPS	$5.40	$14.17
FCF margin	35.5%	50.3%
ROE	25.4%	82.9%
Debt / equity	3.3×	4.4×
Market cap	$78.54B	$83.40B
P/E (TTM)	27.2×	15.3×

Fundamentals are from each company’s SEC filings (AMT FY2025, SPG FY2025). P/E and market cap are derived from recent market prices and update daily.

Five-year trend (as reported)

Revenue	FY2021	FY2022	FY2023	FY2024	FY2025
AMT	$9.36B	$9.65B	$10.01B	$10.13B	$10.64B
SPG	$5.12B	$5.29B	$5.66B	$5.96B	$6.36B

Net income	FY2021	FY2022	FY2023	FY2024	FY2025
AMT	$2.57B	$1.70B	$1.37B	$2.28B	$2.63B
SPG	$2.57B	$2.45B	$2.62B	$2.73B	$5.36B

Operating margin	FY2021	FY2022	FY2023	FY2024	FY2025
AMT	33.5%	28.4%	31.2%	44.6%	45.5%
SPG	47.2%	48.8%	49.6%	51.9%	49.9%

Peer standing

Where each company ranks among the 165 REITs, on the same scale. Each figure is ranked only against peers that report it. Percentiles describe position in the distribution, not a rating.

Metric	AMT	SPG
Operating margin	45.5%69th percentile of 81	49.9%78th percentile of 81
Net margin	24.7%70th percentile of 156	84.3%99th percentile of 156
FCF margin	35.5%73rd percentile of 27	50.3%88th percentile of 27
Revenue growth (YoY)	+5.1%59th percentile of 161	+6.7%66th percentile of 161
ROE	25.4%96th percentile of 141	82.9%Highest of 141
P/E (TTM)	27.2×44th percentile of 108	15.3×13th percentile of 108
Debt / equity	3.27×89th percentile of 99	4.39×92nd percentile of 99
Short interest (days to cover)	1.92d21st percentile of 154	3.14d46th percentile of 154

Short interest

FINRA settlement data	AMT	SPG
Shares sold short	7.7M	10.8M
Change vs prior settlement	-14.5%	+17.0%
Days to cover	1.92	3.14
As of settlement	2026-06-30	2026-06-30

Source: FINRA Consolidated Short Interest. FINRA is the owner and source of the FINRA-supplied data; republishing or redistributing it is not permitted. Not presented as a percentage of float. No FINRA endorsement of this product is implied.

Insider activity (last 90 days)

Form 4 open-market activity	AMT	SPG
Buys	0	28 ($533,052)
Sells	2 ($173,092)	0

Open-market purchases and sales reported on SEC Form 4 (grants, exercises and tax withholding excluded). For context, about 16% of covered companies saw any open-market insider buy in a 90-day window.

Held by the same investors

7 tracked 13F managers hold both American Tower Corp /ma/ and Simon Property Group as of their latest quarterly filings: AQR Capital Management, Bridgewater Associates, Citadel Advisors, D. E. Shaw, Gotham Asset Management, Millennium Management, Two Sigma Investments. See which superinvestors hold your own portfolio with the smart money checker.

Go deeper

AMERICAN TOWER CORP /MA/ (AMT)

Full statements, filings, ownership and peer ranks →

SIMON PROPERTY GROUP INC. (SPG)

Full statements, filings, ownership and peer ranks →

AMT vs DLR AMT vs EQIX AMT vs O AMT vs PLD AMT vs PSA AMT vs WELL All reit stocks →All comparisons →

Track AMT and SPG

Get an alert when either company files something material, see which superinvestors own them, and ask their filings a question with cited answers.

Start monitoring free

Includes one free filing-grounded research answer. Or check your whole portfolio, no account needed.

Data sourced from SEC EDGAR (public domain). Figures are as-reported and may be unaudited or restated; verify against the source filings before relying on them. Comparisons are descriptive (higher or lower on a reported figure), not a rating or a recommendation. Informational only. Not investment advice.