More in U.S. say healthcare is most important problem
This is up from 7% in June, but similar to the 18% recorded in May, when the House of Representatives passed its version of a bill to repeal the Affordable Care Act (ACA).
These findings represent the highest percentages mentioning this issue since 2013, during the troubled roll out of the ACA.
The latest figures, recorded in a July 5-9 Gallup poll, come as the percentage of national adults without health insurance rose in the second quarter of 2017.
Meanwhile, Americans are conflicted on the best approach to healthcare reform - as are the members of Congress.
Mentions of healthcare as a national problem have heightened when the government has tackled the issue in the past.
Most notably, one in four Americans mentioned it in August and September of 2009, as angry constituents voiced their displeasure with the ACA in town hall meetings.
Mentions of healthcare as the nation's top problem were also high in 1993 and 1994 as the Clinton administration attempted - unsuccessfully - to tackle healthcare reform.
Democrats (22%) are more than twice as likely to name healthcare as the biggest problem as Republicans (8%), while 17% of independents say healthcare as the greatest challenge the country faces.
Since President Donald Trump was elected in November, Democrats have been most likely to list the issue as a major problem.
All party groups are more likely now than in June to say healthcare is the most important problem, but the increases are larger among Democrats (nine percentage points) and independents (11 points) than among Republicans (five points). ■