Overflow is a specialty coffee shop at 11 Colquhoun Square in Helensburgh, opened by Graeme Shearer on 29 March 2024. Shearer previously ran Common Ground in Dumbarton and worked at Space Speciality Coffee House in Glasgow before setting up on his own in Helensburgh's main square. The shop serves coffee from a rotating list of roasters alongside pastries and light bakes, in a small, plainly finished room with counter seating rather than a full dining menu. It trades seven days a week from 9am to 4pm. Early in its first year the shop closed briefly for a repaint before reopening a few days later, and reviews through 2025 and into 2026 show it continuing to trade steadily as a neighbourhood coffee spot rather than a tourist-facing café. Overflow is independently owned by Shearer, with no other branches, distinct from his earlier Dumbarton business, which he no longer runs.
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