Paris rain is not the kind of rain that cancels plans. It's a steady grey drizzle that starts in October and shows up most weeks until April. You learn to dress for it or you stay inside for half the year. Dating through Paris weather is mostly a matter of knowing which places absorb a wet afternoon gracefully and which leave you standing under an awning waiting for a table.
The covered passages of the 2nd
The 19th-century passages couverts are the most underused date asset in Paris. Passage des Panoramas, Passage Jouffroy, and Passage Verdeau form a near-continuous indoor walk from Boulevard Montmartre up to Rue de la Grange Batelière. You can spend two hours moving through them without seeing the sky.
Passage des Panoramas is the oldest and the most alive. Stamp dealers, old postcard shops, a few good wine bars including Racines and Caffè Stern. Cross Boulevard Montmartre into Passage Jouffroy and you're suddenly in a Victorian arcade with a wax museum entrance, a walking-stick shop that's been there since 1834, and the Hôtel Chopin tucked at the end. Passage Verdeau, across Rue de la Grange Batelière, has the antique book dealers.
This is a date that costs nothing if you don't buy anything, which you won't be able to resist doing.
The Musée de la Vie Romantique and a hot chocolate
The Musée de la Vie Romantique in the 9th is free for the permanent collection and almost always empty. It's at the end of a small cobbled lane off Rue Chaptal, in what used to be the painter Ary Scheffer's house, and the rooms are small enough that you actually look at things instead of drifting through them.
The garden café is closed in winter, but the museum sits a five-minute walk from Rose Bakery on Rue des Martyrs, which does the best hot chocolate in the 9th, and a ten-minute walk from KB Caféshop on Avenue Trudaine if you want filter coffee instead. The whole loop is well under twenty euros and it kills three hours.
Cinema in the 5th
Paris still has a serious repertory cinema culture. Le Champo, La Filmothèque, and Le Reflet Médicis are within three blocks of each other on Rue des Écoles and Rue Champollion in the 5th, and between them they show old prints of everything from Truffaut to Kurosawa most days of the week. Tickets are around nine euros, less with a UGC or MK2 pass.
A rainy afternoon double feature with a coffee in between at Le Verre à Pied on Rue Mouffetard is one of the better dates available in this city for under thirty euros. Check the schedule at La Cinémathèque in Bercy too if you want something more serious; the building is by Frank Gehry and the programming is genuinely curated by people who love film.
The Marché des Enfants Rouges with no plan
The oldest covered market in Paris, on Rue de Bretagne in the 3rd, is fully roofed and full of food stalls. When it rains, the locals show up and lunch becomes a two-hour project. The Moroccan stand has a tagine that will outlast the weather, and the Italian counter does a decent plate of pasta for around twelve euros.
After lunch, walk south through the upper Marais, ducking into shops on Rue Charlot and Rue de Poitou. Most of the galleries are free. Empreintes on Rue de Picardie is a craft concept store with three floors and a café in the basement, which is exactly the kind of place that holds up when the rain gets heavier.
A long lunch at a bistro that doesn't rush you
Some bistros in Paris will turn your table in 90 minutes and some will let you sit until they reopen for dinner. The second category is what you want when it's raining. Le Petit Vendôme on Rue des Capucines is a sandwich place at the bar but the dining room behind does a proper three-course lunch. Chez Georges on Rue du Mail is louder and more expensive but they will not move you. Bistrot Paul Bert in the 11th is the classic answer.
Order the menu du midi, ask for a half bottle, and watch the windows steam up. This is what Parisians actually do on rainy Saturdays, which is why the rooms are full of regulars and not tourists.
When it really pours: the bouquinistes are closed, but the BHV is open
If the rain turns serious, the bouquinistes along the Seine close their green boxes and there's nothing to do on the quais. Walk to BHV on Rue de Rivoli instead. The basement hardware department is famously a Paris institution, the rooftop bar is open year-round and has a heated terrace, and the building absorbs a couple of hours easily. It's not romantic exactly, but it's specific to Paris in a way that an afternoon at a chain café isn't.
The other true rainy-day move is the Grande Galerie de l'Évolution at the Jardin des Plantes. The taxidermied procession of animals across the main hall is one of the strangest, most quietly beautiful interiors in the city. Twelve euros, two hours, and you'll both leave with something to talk about.