Seaside crowfoot is a prostrate forb, 5-15cm tall, with a smooth stem. It has few flowers with 3-5mm petals, that scarcely surpass the sepals, of which there are usually 5, rarely more. Achenes are longitudinally nerved, 1.5-2mm, numerous in a short-cylindric head to 12mm. Mostly basal, blades cordate-ovate to ovate or kidney-shaped, 5-25mm, rounded above, usually cordate below, petioles 2-5cm.
Its cordate-ovate to ovate or kidney-shaped principal leaves differentiate it from similar species.