Ameren Illinois Co (AILIO) stock
AILIOOTCElectric & Other Services CombinedFiscal year ends December 31Also trades as AILIH, AILIM, AILIN, AILIP, AILLI, AILLM, AILLN, AILLO, AILLP
Last filing: 10-Q on Aug 3, 2026
$66.00+0.00 (0.00%)
Close on Oct 19, 2026Market cap –P/E –Yield –
Price history
Ameren Illinois share prices for every month, newest first. Adjusted for stock splits, not for dividends.
Close, Oct 19, 2026
$66.00
0.00% on the day
52-week range
$65.40 – $73.00
-9.6% from the high
Change over 52 weeks
-2.9%
From $68.00 on Oct 17, 2025
Average volume
10
Shares a day, last 90 sessions
| Month | Open | High | Low | Close | Change | Volume |
|---|---|---|---|---|---|---|
| Oct 2026 | $65.90 | $66.00 | $65.40 | $66.00 | +0.15% | 500 |
| Sep 2026 | $72.00 | $72.00 | $65.90 | $65.90 | -8.47% | 210 |
| Aug 2026 | $70.89 | $72.00 | $70.89 | $72.00 | +1.57% | 100 |
| Jul 2026 | $70.89 | $70.89 | $70.89 | $70.89 | 0.00% | 0 |
| Jun 2026 | $70.89 | $70.89 | $70.89 | $70.89 | 0.00% | 100 |
| May 2026 | $70.90 | $70.90 | $66.03 | $70.89 | -0.01% | 451 |
| Apr 2026 | $71.69 | $72.00 | $70.90 | $70.90 | -1.10% | 201 |
| Mar 2026 | $69.90 | $71.69 | $69.90 | $71.69 | +2.57% | 120 |
| Feb 2026 | $69.10 | $71.00 | $69.10 | $69.90 | +1.15% | 900 |
| Jan 2026 | $70.00 | $70.00 | $68.30 | $69.10 | -1.29% | 258 |
| Dec 2025 | $73.00 | $73.00 | $70.00 | $70.00 | -4.11% | 435 |
| Nov 2025 | $73.00 | $73.00 | $73.00 | $73.00 | 0.00% | 0 |
| Oct 2025 | $68.00 | $73.00 | $68.00 | $73.00 | +7.35% | 875 |
| Sep 2025 | $67.00 | $70.00 | $67.00 | $68.00 | +1.49% | 370 |
| Aug 2025 | $69.98 | $69.98 | $67.00 | $67.00 | -4.26% | 188 |
| Jul 2025 | $69.98 | $69.98 | $69.98 | $69.98 | 0.00% | 0 |
| Jun 2025 | $71.00 | $71.00 | $67.00 | $69.98 | -1.44% | 959 |
| May 2025 | $67.93 | $71.00 | $67.93 | $71.00 | +4.52% | 250 |
| Apr 2025 | $69.66 | $69.66 | $67.93 | $67.93 | -2.48% | 219 |
| Mar 2025 | $69.75 | $69.75 | $69.66 | $69.66 | -0.13% | 100 |
| Feb 2025 | $71.25 | $71.25 | $69.75 | $69.75 | -2.11% | 104 |
| Jan 2025 | $71.25 | $71.25 | $71.25 | $71.25 | 0.00% | 0 |
| Dec 2024 | $71.00 | $71.25 | $69.00 | $71.25 | +0.35% | 603 |
| Nov 2024 | $73.75 | $73.75 | $71.00 | $71.00 | -3.73% | 200 |
| Oct 2024 | $71.38 | $73.75 | $71.38 | $73.75 | +3.32% | 100 |
| Sep 2024 | $69.74 | $71.38 | $69.74 | $71.38 | +2.35% | 500 |
| Aug 2024 | $69.23 | $69.74 | $69.23 | $69.74 | +0.74% | 300 |
| Jul 2024 | $68.00 | $69.23 | $67.25 | $69.23 | +1.81% | 800 |
| Jun 2024 | $71.00 | $71.00 | $67.40 | $68.00 | -4.23% | 1,000 |
| May 2024 | $71.00 | $71.00 | $71.00 | $71.00 | 0.00% | 0 |
| Apr 2024 | $71.00 | $71.00 | $71.00 | $71.00 | 0.00% | 0 |
| Mar 2024 | $71.00 | $71.00 | $71.00 | $71.00 | 0.00% | 0 |
| Feb 2024 | $71.00 | $71.00 | $71.00 | $71.00 | 0.00% | 0 |
| Jan 2024 | $66.52 | $71.00 | $66.52 | $71.00 | +6.73% | 200 |
| Dec 2023 | $65.75 | $69.75 | $64.50 | $66.52 | +1.17% | 2,100 |
| Nov 2023 | $63.00 | $65.75 | $63.00 | $65.75 | +4.37% | 100 |
| Oct 2023 | $80.50 | $80.50 | $63.00 | $63.00 | -21.74% | 500 |
| Sep 2023 | $80.50 | $80.50 | $80.50 | $80.50 | 0.00% | 0 |
| Aug 2023 | $80.50 | $80.50 | $80.50 | $80.50 | 0.00% | 0 |
| Jul 2023 | $80.50 | $80.50 | $80.50 | $80.50 | 0.00% | 0 |
| Jun 2023 | $79.00 | $80.50 | $77.20 | $80.50 | +1.90% | 500 |
| May 2023 | $75.55 | $79.00 | $74.00 | $79.00 | +4.57% | 500 |
| Apr 2023 | $85.00 | $85.00 | $75.55 | $75.55 | -11.12% | 200 |
| Mar 2023 | $77.00 | $85.00 | $77.00 | $85.00 | +10.39% | 400 |
| Feb 2023 | $77.00 | $77.00 | $77.00 | $77.00 | 0.00% | 0 |
| Jan 2023 | $77.00 | $77.00 | $77.00 | $77.00 | 0.00% | 0 |
| Dec 2022 | $87.01 | $87.01 | $77.00 | $77.00 | -11.50% | 2,700 |
| Nov 2022 | $87.01 | $87.01 | $87.01 | $87.01 | 0.00% | 0 |
| Oct 2022 | $87.01 | $87.01 | $87.01 | $87.01 | 0.00% | 0 |
| Sep 2022 | $87.01 | $87.01 | $87.01 | $87.01 | 0.00% | 0 |
| Aug 2022 | $87.01 | $87.01 | $87.01 | $87.01 | 0.00% | 0 |
| Jul 2022 | $87.01 | $87.01 | $87.01 | $87.01 | 0.00% | 0 |
| Jun 2022 | $87.01 | $87.01 | $87.01 | $87.01 | 0.00% | 0 |
| May 2022 | $86.00 | $87.01 | $86.00 | $87.01 | +1.17% | 900 |
| Apr 2022 | $95.00 | $95.00 | $86.00 | $86.00 | -9.47% | 1,600 |
| Mar 2022 | $96.00 | $96.00 | $95.00 | $95.00 | -1.04% | 100 |
| Feb 2022 | $98.10 | $98.10 | $96.00 | $96.00 | -2.14% | 300 |
| Jan 2022 | $98.10 | $98.10 | $98.10 | $98.10 | 0.00% | 0 |
| Dec 2021 | $98.10 | $98.10 | $98.10 | $98.10 | 0.00% | 0 |
| Nov 2021 | $97.51 | $99.25 | $97.51 | $98.10 | +0.61% | 500 |
| Oct 2021 | $97.51 | $97.51 | $97.51 | $97.51 | 0.00% | 0 |
| Sep 2021 | $97.01 | $97.51 | $97.01 | $97.51 | +0.52% | 100 |
| Aug 2021 | $100.40 | $100.40 | $97.01 | $97.01 | -3.38% | 100 |
| Jul 2021 | $95.86 | $100.40 | $95.86 | $100.40 | +4.74% | 800 |
| Jun 2021 | $98.00 | $98.00 | $95.86 | $95.86 | -2.18% | 100 |
| May 2021 | $93.00 | $98.00 | $93.00 | $98.00 | +5.38% | 300 |
| Apr 2021 | $101.50 | $101.50 | $93.00 | $93.00 | -8.37% | 200 |
| Mar 2021 | $101.50 | $101.50 | $101.50 | $101.50 | 0.00% | 0 |
| Feb 2021 | $101.50 | $101.50 | $101.50 | $101.50 | 0.00% | 400 |
| Jan 2021 | $100.00 | $101.50 | $100.00 | $101.50 | +1.50% | 100 |
| Dec 2020 | $100.00 | $100.00 | $100.00 | $100.00 | 0.00% | 0 |
| Nov 2020 | $100.00 | $100.01 | $100.00 | $100.00 | 0.00% | 300 |
| Oct 2020 | $100.00 | $100.00 | $100.00 | $100.00 | 0.00% | 0 |
| Sep 2020 | $100.00 | $100.00 | $100.00 | $100.00 | 0.00% | 0 |
| Aug 2020 | $100.00 | $100.00 | $100.00 | $100.00 | 0.00% | 0 |
| Jul 2020 | $100.00 | $100.00 | $100.00 | $100.00 | 0.00% | 0 |
| Jun 2020 | $99.75 | $100.50 | $99.75 | $100.00 | +0.24% | 3,000 |
| May 2020 | $100.25 | $100.25 | $99.76 | $99.76 | -0.49% | 200 |
| Apr 2020 | $100.25 | $100.25 | $100.25 | $100.25 | 0.00% | 0 |
| Mar 2020 | $100.60 | $100.60 | $100.25 | $100.25 | -0.35% | 300 |
| Feb 2020 | $100.60 | $100.60 | $100.60 | $100.60 | 0.00% | 0 |
| Jan 2020 | $98.50 | $100.60 | $98.50 | $100.60 | +2.13% | 200 |
| Dec 2019 | $98.50 | $98.50 | $98.50 | $98.50 | 0.00% | 300 |
| Nov 2019 | $100.00 | $100.00 | $97.00 | $98.50 | -1.50% | 200 |
| Oct 2019 | $100.00 | $100.00 | $100.00 | $100.00 | 0.00% | 100 |
| Sep 2019 | $91.00 | $101.00 | $91.00 | $100.00 | +9.89% | 900 |
| Aug 2019 | $91.00 | $97.00 | $91.00 | $91.00 | 0.00% | 700 |
| Jul 2019 | $97.00 | $150.00 | $91.00 | $91.00 | -6.19% | 500 |
| Jun 2019 | $97.00 | $97.00 | $97.00 | $97.00 | 0.00% | 0 |
| May 2019 | $97.00 | $97.00 | $97.00 | $97.00 | 0.00% | 0 |
| Apr 2019 | $97.00 | $97.00 | $97.00 | $97.00 | 0.00% | 0 |
| Mar 2019 | $97.00 | $97.00 | $97.00 | $97.00 | 0.00% | 0 |
| Feb 2019 | $95.00 | $97.00 | $95.00 | $97.00 | +2.11% | 600 |
| Jan 2019 | $95.00 | $95.00 | $95.00 | $95.00 | 0.00% | 100 |
| Dec 2018 | $95.00 | $95.00 | $94.00 | $95.00 | 0.00% | 300 |
| Nov 2018 | $96.93 | $96.93 | $93.05 | $95.00 | -1.99% | 900 |
| Oct 2018 | $96.93 | $96.93 | $96.93 | $96.93 | 0.00% | 0 |
| Sep 2018 | $99.00 | $99.00 | $96.93 | $96.93 | -2.09% | 300 |
| Aug 2018 | $99.00 | $99.00 | $99.00 | $99.00 | 0.00% | 0 |
| Jul 2018 | $99.00 | $99.00 | $99.00 | $99.00 | 0.00% | 0 |
| Jun 2018 | $99.00 | $99.00 | $99.00 | $99.00 | 0.00% | 0 |
| May 2018 | $99.00 | $99.00 | $99.00 | $99.00 | 0.00% | 0 |
| Apr 2018 | $95.50 | $99.00 | $95.50 | $99.00 | +3.66% | 600 |
| Mar 2018 | $96.10 | $96.10 | $95.50 | $95.50 | -0.62% | 0 |
| Feb 2018 | $96.10 | $96.10 | $96.10 | $96.10 | 0.00% | 100 |
| Jan 2018 | $98.20 | $98.20 | $96.10 | $96.10 | -2.14% | 100 |
| Dec 2017 | $98.20 | $98.20 | $98.20 | $98.20 | 0.00% | 0 |
| Nov 2017 | $98.20 | $98.20 | $98.20 | $98.20 | 0.00% | 0 |
| Oct 2017 | $98.20 | $98.20 | $98.20 | $98.20 | 0.00% | 0 |
| Sep 2017 | $98.20 | $98.20 | $98.20 | $98.20 | 0.00% | 0 |
| Aug 2017 | $98.20 | $98.20 | $98.20 | $98.20 | 0.00% | 0 |
| Jul 2017 | $96.75 | $98.20 | $96.75 | $98.20 | +1.50% | 200 |
| Jun 2017 | $96.75 | $96.75 | $96.75 | $96.75 | 0.00% | 0 |
| May 2017 | $95.10 | $96.75 | $95.10 | $96.75 | +1.74% | 1,100 |
| Apr 2017 | $102.01 | $102.01 | $95.10 | $95.10 | -6.77% | 200 |
| Mar 2017 | $102.01 | $102.01 | $102.01 | $102.01 | 0.00% | 0 |
| Feb 2017 | $102.01 | $102.01 | $102.01 | $102.01 | 0.00% | 100 |
| Jan 2017 | $99.51 | $102.01 | $99.51 | $102.01 | +2.51% | 200 |
| Dec 2016 | $99.51 | $99.51 | $99.51 | $99.51 | 0.00% | 0 |
| Nov 2016 | $100.49 | $100.49 | $99.51 | $99.51 | -0.98% | 100 |
| Oct 2016 | $100.49 | $100.49 | $100.49 | $100.49 | 0.00% | 0 |
| Sep 2016 | $99.00 | $100.49 | $99.00 | $100.49 | +1.51% | 100 |
| Aug 2016 | $99.00 | $99.00 | $99.00 | $99.00 | 0.00% | 0 |
| Jul 2016 | $99.00 | $99.00 | $99.00 | $99.00 | 0.00% | 0 |
| Jun 2016 | $96.50 | $99.00 | $96.50 | $99.00 | +2.59% | 1,400 |
| May 2016 | $96.50 | $96.50 | $96.50 | $96.50 | 0.00% | 0 |
| Apr 2016 | $96.50 | $96.50 | $96.50 | $96.50 | 0.00% | 0 |
| Mar 2016 | $96.50 | $96.50 | $96.50 | $96.50 | 0.00% | 0 |
| Feb 2016 | $95.00 | $96.50 | $95.00 | $96.50 | +1.58% | 800 |
| Jan 2016 | $99.00 | $99.00 | $95.00 | $95.00 | -4.04% | 600 |
| Dec 2015 | $99.25 | $100.00 | $97.00 | $99.00 | -0.25% | 2,100 |
| Nov 2015 | $99.25 | $99.25 | $99.25 | $99.25 | 0.00% | 0 |
| Oct 2015 | $95.50 | $99.25 | $95.50 | $99.25 | +3.93% | 2,300 |
| Sep 2015 | $95.50 | $95.50 | $95.50 | $95.50 | 0.00% | 0 |
| Aug 2015 | $99.75 | $99.75 | $92.45 | $95.50 | -4.26% | 1,100 |
| Jul 2015 | $99.75 | $99.75 | $99.75 | $99.75 | 0.00% | 0 |
| Jun 2015 | $98.25 | $99.75 | $98.25 | $99.75 | +1.53% | 4,900 |
| May 2015 | $98.25 | $98.25 | $98.25 | $98.25 | 0.00% | 0 |
| Apr 2015 | $98.25 | $98.25 | $98.25 | $98.25 | 0.00% | 0 |
| Mar 2015 | $98.25 | $98.25 | $98.25 | $98.25 | 0.00% | 0 |
| Feb 2015 | $98.25 | $98.25 | $98.25 | $98.25 | 0.00% | 0 |
| Jan 2015 | $95.93 | $98.25 | $95.93 | $98.25 | +2.42% | 1,200 |
| Dec 2014 | $95.93 | $95.93 | $95.93 | $95.93 | 0.00% | 100 |
| Nov 2014 | $95.93 | $95.93 | $95.93 | $95.93 | 0.00% | 500 |
| Oct 2014 | $97.75 | $98.50 | $95.93 | $95.93 | -1.10% | 2,000 |
| Sep 2014 | $92.00 | $97.00 | $92.00 | $97.00 | +5.43% | 400 |
| Aug 2014 | $93.00 | $94.00 | $92.00 | $92.00 | -1.08% | 600 |
| Jul 2014 | $97.75 | $97.75 | $91.00 | $93.00 | -4.86% | 300 |
| Jun 2014 | $92.00 | $97.75 | $92.00 | $97.75 | +6.25% | 300 |
| May 2014 | $92.00 | $92.00 | $92.00 | $92.00 | 0.00% | 0 |
| Apr 2014 | $98.50 | $98.50 | $92.00 | $92.00 | -6.60% | 100 |
| Mar 2014 | $96.25 | $98.75 | $96.00 | $98.50 | +2.34% | 7,400 |
| Feb 2014 | $96.25 | $96.25 | $96.25 | $96.25 | 0.00% | 0 |
| Jan 2014 | $96.25 | $96.25 | $96.25 | $96.25 | 0.00% | 0 |
| Dec 2013 | $96.68 | $96.68 | $94.75 | $96.25 | -0.44% | 5,800 |
| Nov 2013 | $96.68 | $96.68 | $96.68 | $96.68 | 0.00% | 0 |
| Oct 2013 | $96.68 | $96.68 | $96.68 | $96.68 | 0.00% | 0 |
| Sep 2013 | $96.68 | $96.68 | $96.68 | $96.68 | 0.00% | 0 |
| Aug 2013 | $96.68 | $96.68 | $96.68 | $96.68 | 0.00% | 0 |
| Jul 2013 | $99.00 | $99.00 | $96.68 | $96.68 | -2.34% | 300 |
| Jun 2013 | $102.25 | $102.25 | $98.00 | $99.00 | -3.18% | 1,200 |
| May 2013 | $101.50 | $102.25 | $101.25 | $102.25 | +0.74% | 2,200 |
| Apr 2013 | $94.01 | $101.50 | $94.01 | $101.50 | +7.97% | 8,700 |
| Mar 2013 | $100.00 | $100.00 | $94.01 | $94.01 | -5.99% | 100 |
| Feb 2013 | $99.00 | $100.00 | $99.00 | $100.00 | +1.01% | 6,000 |
| Jan 2013 | $99.00 | $99.00 | $99.00 | $99.00 | 0.00% | 0 |
| Dec 2012 | $99.00 | $99.00 | $99.00 | $99.00 | 0.00% | 0 |
| Nov 2012 | $99.00 | $99.00 | $99.00 | $99.00 | – | 0 |
Seasonality
AILIO return in each calendar month over the last 10 years, including dividends. The current month runs to the latest close.
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Average | 2.2% | -0.1% | 1.1% | -2.3% | 1.7% | -0.6% | 1.4% | -0.5% | 0.4% | 0.2% | -0.2% | -1.6% |
| Months up | 9 of 10 | 2 of 10 | 2 of 10 | 5 of 10 | 5 of 10 | 2 of 10 | 9 of 10 | 2 of 10 | 4 of 10 | 9 of 10 | 2 of 9 | 2 of 9 |
| 2026 | 0.3% | 1.2% | 2.6% | 0.4% | -0.0% | 0.0% | 1.5% | 1.6% | -8.5% | 1.8% | ||
| 2025 | 1.5% | -2.1% | -0.1% | -1.0% | 4.5% | -1.4% | 1.5% | -4.3% | 1.5% | 9.1% | 0.0% | -4.1% |
| 2024 | 8.4% | 0.0% | 0.0% | 1.5% | 0.0% | -4.2% | 3.4% | 0.7% | 2.4% | 4.8% | -3.7% | 0.4% |
| 2023 | 1.4% | 0.0% | 10.4% | -9.8% | 4.6% | 1.9% | 1.3% | 0.0% | 0.0% | -20.4% | 4.4% | 1.2% |
| 2022 | 1.1% | -2.1% | -1.0% | -8.4% | 1.2% | 0.0% | 1.2% | 0.0% | 0.0% | 1.2% | 0.0% | -11.5% |
| 2021 | 2.6% | 0.0% | 0.0% | -7.4% | 5.4% | -2.2% | 5.9% | -3.4% | 0.5% | 1.1% | 0.6% | 0.0% |
| 2020 | 3.2% | 0.0% | -0.3% | 1.1% | -0.5% | 0.2% | 1.1% | 0.0% | 0.0% | 1.1% | 0.0% | 0.0% |
| 2019 | 1.1% | 2.1% | 0.0% | 1.1% | 0.0% | 0.0% | -5.5% | 0.0% | 9.9% | 1.1% | -1.5% | 0.0% |
| 2018 | -1.1% | 0.0% | -0.6% | 4.8% | 0.0% | 0.0% | 1.1% | 0.0% | -2.1% | 1.1% | -2.0% | 0.0% |
| 2017 | 3.6% | 0.0% | 0.0% | -5.8% | 1.7% | 0.0% | 2.6% | 0.0% | 0.0% | 1.1% | 0.0% | 0.0% |