v3.25.4
Long-Term Debt (Tables)
12 Months Ended
Dec. 31, 2025
Long-Term Debt, Current and Noncurrent [Abstract]  
Schedule of Long-Term Debt
Our long-term debt as of December 31, 2025 and 2024 is as follows:
Long-term debt type
Maturity as of December 31, 2025
Weighted average interest rate (%)
Outstanding balance as of December 31, (in millions)
20252024
Senior notes:
NiSourceAugust 20250.950 %$ $1,250.0 
NiSourceMay 20273.490 %1,000.0 1,000.0 
NiSourceDecember 20276.780 %3.0 3.0 
NiSourceMarch 20285.250 %1,050.0 1,050.0 
NiSource
July 20295.200 %600.0 600.0 
NiSourceSeptember 20292.950 %750.0 750.0 
NiSourceMay 20303.600 %1,000.0 1,000.0 
NiSourceFebruary 20311.700 %750.0 750.0 
NiSourceJune 20335.400 %450.0 450.0 
NiSource
April 20345.350 %650.0 650.0 
NiSourceJuly 20355.350 %900.0 — 
NiSource
December 20406.250 %152.6 152.6 
NiSourceJune 20415.950 %347.4 347.4 
NiSourceFebruary 20425.800 %250.0 250.0 
NiSourceFebruary 20435.250 %500.0 500.0 
NiSourceFebruary 20444.800 %750.0 750.0 
NiSourceFebruary 20455.650 %500.0 500.0 
NiSourceMay 20474.375 %1,000.0 1,000.0 
NiSourceMarch 20483.950 %750.0 750.0 
NiSourceJune 20525.000 %350.0 350.0 
NiSourceApril 20555.850 %1,500.0 — 
Total senior notes$13,253.0 $12,103.0 
Junior subordinated notes:
NiSource
November 20546.950 %$500.0 $500.0 
NiSourceMarch 20556.375 %500.0 500.0 
NiSourceJuly 20565.750 %1,000.0 — 
Total junior subordinated notes
$2,000.0 $1,000.0 
Medium term notes:
NiSource
May 2027
7.990 %$29.0 $29.0 
NIPSCO
June 2027 to August 2027
7.644 %58.0 58.0 
Columbia of MassachusettsDecember 20256.430 % 10.0 
Columbia of Massachusetts
February 2028
6.260 %5.0 5.0 
Total medium term notes$92.0 $102.0 
Finance leases:
NiSource Corporate Services
January 2026 to September 2027
4.350 %$5.0 $14.6 
NIPSCO
December 2027 to December 2063
5.480 %165.5 124.3 
Columbia of Ohio
December 2035 to March 2052
6.110 %81.7 85.6 
Columbia of Virginia
July 2029 to November 2039
5.620 %16.2 15.2 
Columbia of Kentucky
May 2027
5.360 %0.1 0.1 
Columbia of Pennsylvania
March 2030 to May 2035
4.430 %5.5 6.4 
Total finance leases$274.0 $246.2 
Less: Unamortized issuance costs and discounts
(141.5)(95.5)
Less: Current portion of long term debt
(19.7)(1,281.2)
Total Long-Term Debt$15,457.8 $12,074.5