Exact federal listing answer
Is Porter Flats Apartments on the National Register?
Yes · NPS status: Listed
Yes. Reference 92001761 is listed.
Yes. The U.S. National Park Service listed-properties dataset through May 22, 2026 identifies Porter Flats Apartments as Listed in the National Register of Historic Places under reference 92001761.
Federal statusListed
National Register reference92001761
Listed dateJanuary 14, 1993
Property categoryBuilding
Published address335 N. Ewing St.
LocalityHelena, Lewis and Clark County, Montana
Significance levelLocal
Published acreage0.9
Exact answer boundaryThis confirms the named federal record only.
It does not prove that another address lies inside this property or district, establish local landmark status, decide preservation review, define a legal boundary, or describe ownership or current condition.
Why the wording is date-boundedThe answer reflects the NPS dataset published through May 22, 2026 and a live NPS GIS Listed-status cross-check made September 20, 2026. NPS notes that spatial points and polygons may need correction and are not legal documents.
Additional published fields
Areas of significance: EXPLORATION/SETTLEMENT, ARCHITECTURE.
Same locality
Other released Helena records.
Each linked page answers a separate named federal record.