Saint Luc sits at 1,650 metres on a sunny balcony above Val d'Anniviers in the canton of Valais, with the village positioned on the eastern flank of the valley opposite the larger Grimentz-Zinal ski area. The valley extends southward from the Rhône Valley town of Sierre, surrounded by 4,000-metre peaks including the Weisshorn, Zinalrothorn, and Dent Blanche forming the Imperial Crown range. The municipality of Anniviers was formed in 2009 by merging six villages including Saint Luc, Chandolin, Grimentz, Vissoie, Ayer, and Saint-Jean. The geographic position between Verbier, Crans-Montana, and Zermatt places Saint Luc in one of Switzerland's less-commercialised ski valleys.

Vissoie, the valley's central hub at 1,204 metres, lies five kilometres downvalley and serves as the postbus interchange connecting all Val d'Anniviers resorts. Sierre, the nearest major town at 525 metres in the Rhône Valley, sits 22 kilometres by road and serves as the primary transport gateway with rail connections and regional amenities. The village of Chandolin, positioned at 2,000 metres and one of Europe's highest year-round settlements, shares the ski area and sits approximately 15 minutes by bus from Saint Luc. The region lies in French-speaking Valais, with the linguistic border to German-speaking Wallis running along the mountain ridges to the east.

Road access from Geneva follows the A9 motorway via Lausanne to Sierre, then climbs steeply through hairpin bends up the valley for approximately 22 kilometres to Saint Luc. The journey from Geneva takes two hours by car, covering 185 kilometres, whilst Zurich lies 3.5 to four hours away via the A9. The A9 motorway continues eastward to Brig and the Simplon Pass, positioning Val d'Anniviers on major trans-Alpine routes. Mountain roads require winter tyres between November and March, with postbuses expertly navigating the tight switchbacks using distinctive sing-song horns to alert oncoming traffic.

Sion Airport lies approximately 45 minutes away and offers seasonal flights from London and Portugal during winter and summer. Geneva Airport, 185 kilometres distant, provides the most international connections with direct trains to Sierre in under 2.5 hours. From Sierre station, postbus route 451 runs hourly to Vissoie, where passengers change to connecting services for Saint Luc, with total journey time around one hour. Zurich Airport lies roughly 310 kilometres away with train connections via Bern or direct routes to Sierre taking approximately four hours including the valley bus transfer.