As of March 31, 2018, we carried a total debt balance (including accrued interest) of €4,820.9 million, of which €2,140.6 million principal amount is related to the Senior Secured Fixed Rate Notes with maturities ranging from 2024 through 2028 and €1,787.7 million principal amount is owed under our 2017 Amended Senior Credit Facility. Our total debt balance at March 31, 2018 also included €341.7 million of short-term debt related to our vendor financing program and €16.3 million for the outstanding portion of the 3G mobile spectrum including accrued interest. The remainder primarily represents the capital lease obligations associated with the Interkabel Acquisition.
In March 2018, we used part of our cash and cash equivalents to prepay 10% of Facility AB under our 2017 Amended Senior Credit Facility, of which the lender is Telenet Finance VI Luxembourg S.C.A. ("TFLVI"). TFLVI used the proceeds from the prepayment of 10% of Facility AB to redeem 10% of the original aggregate principal amount of its 4.875% €530.0 million Senior Secured Notes due July 2027.
In March 2018, we successfully issued an additional USD 300.0 million Term Loan ("Facility AL2")under which Telenet Financing USD LLC is the borrowing entity. Facility AL2 carries the same characteristics as the initial Facility AL, which was issued on December 1, 2017. As such, Facility AL2 carries (i) a margin of 2.50% over LIBOR, (ii) a 0% LIBOR floor and (iii) a maturity of March 1, 2026. Facility AL2 was successfully issued at par. In April 2018, Telenet Financing USD LLC borrowed the full USD 300.0 million under Facility AL2 and on-lent the net proceeds of this issuance to Telenet International Finance S.à r.l which used such proceeds, together with existing cash, to prepay Facility V under our 2017 Amended Senior Credit Facility, of which the lender is Telenet Finance V Luxembourg S.C.A. ("TFLV"). TFLV used the proceeds from the prepayment of Facility V to redeem in full its 6.75% €250.0 million Senior Secured Notes due August 2024.
Excluding both the short-term vendor financing commitments (as mentioned above) and lease-related liabilities, we face no debt maturities prior to March 2026 and, as of March 31, 2018, had full access to €689.1 million of undrawn commitments under our revolving credit facilities with certain availabilities up to June 30, 2023. As mentioned, we used the full capacity under Facility AL2 in early April to redeem the €250.0 million Senior Secured Notes, decreasing the availability of undrawn commitments with the same amount
DEBT OVERVIEW AND PAYMENT SCHEDULES
The table below provides an overview of our debt instruments and payment schedule at March 31, 2018.