With an Agile Remaining Estimate Counter plugin you get summarized remaining estimated time by particular group of tasks.
This Atlassian JIRA plugin allows you to see the total sum of remaining estimated time even with tickets’ subtasks in the sprint list.
AREC shows total remaining effort for partially completed issues including Sub-Tasks.
AREC reflects effort for the whole team in both active and future sprints in backlog. Active sprint board reflects remaining effort split by swimlanes.