financial burden
US /faɪˈnæn.ʃəl ˈbɜːr.dən/
UK /faɪˈnæn.ʃəl ˈbɜːr.dən/

1.
a responsibility or obligation that involves a significant amount of money or debt, often causing stress or difficulty
:
•
The high medical bills became a huge financial burden for the family.
•
Taking on that large loan would be a significant financial burden.