AMERICAN TOWER CORP /MA/ (AMT) capitalization
Current snapshot
Annual history
One row per fiscal year (10-K). Market cap uses split-adjusted closing price on the fiscal-year-end date × shares outstanding.
| Period | End | Market Cap |
|---|---|---|
| FY'25 | 2025-12-31 | $82.30B |
| FY'24 | 2024-12-31 | $85.86B |
| FY'23 | 2023-12-31 | $100.85B |
| FY'22 | 2022-12-31 | $98.04B |
| FY'21 | 2021-12-31 | $132.59B |
| FY'20 | 2020-12-31 | $100.13B |
| FY'19 | 2019-12-31 | $102.39B |
| FY'16 | 2016-12-31 | $45.37B |
| FY'15 | 2015-12-31 | $41.01B |
| FY'14 | 2014-12-31 | $39.55B |
| FY'13 | 2013-12-31 | $31.86B |
| FY'12 | 2012-12-31 | $30.85B |
| FY'11 | 2011-12-31 | $24.02B |
| FY'10 | 2010-12-31 | $20.87B |
| FY'09 | 2009-12-31 | $17.58B |
Quarterly history
One row per quarter (10-Q and Q4 from 10-K). Market cap uses split-adjusted closing price on the quarter-end date × shares outstanding.
| Period | End | Market Cap |
|---|---|---|
| Q4'25 | 2025-12-31 | $81.87B |
| Q3'25 | 2025-09-30 | $90.21B |
| Q2'25 | 2025-06-30 | $103.61B |
| Q1'25 | 2025-03-31 | $101.95B |
| Q4'24 | 2024-12-31 | $85.72B |
| Q3'24 | 2024-09-30 | $108.90B |
| Q2'24 | 2024-06-30 | $90.93B |
| Q1'24 | 2024-03-31 | $92.40B |
| Q4'23 | 2023-12-31 | $100.66B |
| Q3'23 | 2023-09-30 | $76.82B |
| Q2'23 | 2023-06-30 | $90.57B |
| Q1'23 | 2023-03-31 | $95.39B |
| Q4'22 | 2022-12-31 | $98.65B |
| Q3'22 | 2022-09-30 | $100.22B |
| Q2'22 | 2022-06-30 | $117.53B |
| Q1'22 | 2022-03-31 | $114.86B |
| Q4'21 | 2021-12-31 | $133.31B |
| Q3'21 | 2021-09-30 | $121.29B |
| Q2'21 | 2021-06-30 | $122.20B |
| Q1'21 | 2021-03-31 | $106.69B |
| Q4'20 | 2020-12-31 | $99.73B |
| Q3'20 | 2020-09-30 | $107.85B |
| Q2'20 | 2020-06-30 | $115.27B |
| Q1'20 | 2020-03-31 | $97.08B |
| Q4'19 | 2019-12-31 | $101.78B |
| Q3'19 | 2019-09-30 | $98.59B |
| Q2'19 | 2019-06-30 | $91.05B |
| Q1'19 | 2019-03-31 | $87.62B |
| Q1'19 | 2018-12-31 | $70.07B |
| Q3'18 | 2018-09-30 | $64.53B |
| Q2'18 | 2018-06-30 | $64.06B |
| Q1'18 | 2018-03-31 | $63.73B |
| Q1'18 | 2017-12-31 | $61.59B |
| Q3'17 | 2017-09-30 | $59.16B |
| Q2'17 | 2017-06-30 | $56.96B |
| Q1'17 | 2017-03-31 | $52.29B |
| Q4'16 | 2016-12-31 | $45.14B |
| Q3'16 | 2016-09-30 | $48.72B |
| Q2'16 | 2016-06-30 | $48.74B |
| Q1'16 | 2016-03-31 | $43.80B |
| Q4'15 | 2015-12-31 | $41.10B |
| Q3'15 | 2015-09-30 | $37.59B |
| Q2'15 | 2015-06-30 | $39.83B |
| Q1'15 | 2015-03-31 | $38.54B |
| Q4'14 | 2014-12-31 | $39.21B |
| Q3'14 | 2014-09-30 | $37.49B |
| Q2'14 | 2014-06-30 | $35.95B |
| Q1'14 | 2014-03-31 | $32.68B |
| Q4'13 | 2013-12-31 | $31.52B |
| Q3'13 | 2013-09-30 | $29.53B |
| Q2'13 | 2013-06-30 | $29.23B |
| Q1'13 | 2013-03-31 | $30.74B |
| Q4'12 | 2012-12-31 | $30.53B |
| Q3'12 | 2012-09-30 | $28.52B |
| Q2'12 | 2012-06-30 | $27.88B |
| Q1'12 | 2012-03-31 | $25.11B |
| Q4'11 | 2011-12-31 | $23.62B |
| Q3'11 | 2011-09-30 | $21.26B |
| Q2'11 | 2011-06-30 | $20.95B |
| Q1'11 | 2011-03-31 | $20.83B |
| Q4'10 | 2010-12-31 | $20.59B |
| Q3'10 | 2010-09-30 | $20.68B |
| Q2'10 | 2010-06-30 | $18.02B |
| Q1'10 | 2010-03-31 | $17.30B |
| Q4'09 | 2009-12-31 | $17.35B |
| Q3'09 | 2009-09-30 | $14.77B |
| Q2'09 | 2009-06-30 | $12.89B |
| Q1'10 | 2009-03-31 | $12.42B |
| Q2'09 | 2008-12-31 | $12.27B |
| Q3'09 | 2008-09-30 | $14.98B |
| Q2'09 | 2008-06-30 | $17.81B |
| Q2'09 | 2007-12-31 | $18.15B |
Methodology
Every figure on this page traces back to SEC EDGAR XBRL company-facts filings (AMT CIK 0001053507), tagged with the us-gaap and dei taxonomies. The only exception is the live market cap tile, which uses the current share price × shares outstanding from a market quote. Historical share prices come from our total-returns daily history (split-adjusted); historical market caps are calibrated against today's share count to correct for SEC retroactive split restatements.
For the exact XBRL concepts and formulas, see the methodology reference for net worth, debt, cash, market cap, enterprise value, net debt, shares outstanding, and the historical-market-cap calibration.