- Because they allow in proportionally less oxygen than standard bottles, magnums slow down oxidation, helping wines — especially age-worthy reds and structured whites — develop more complexity and balance over time.
- While magnums have visual appeal, winemakers and educators emphasize their practical benefits for cellaring, particularly for wines with strong tannins or acidity, such as Cabernet Franc, Barolo, and Champagne.
- While they may not be cheaper per liter, magnums yield about ten glasses, lessen the risk of premature aging, and add impact at the table — making them a smart, intentional choice for both aging and entertaining.
Magnums come with baggage. They’re often perceived as extravagant or meant for collectors — something you’d bring to a big dinner party and leave unfinished. But in practice, the format serves a very different purpose, especially in terms of how wine ages over time. Wanda Mann, a wine educator and the founder of Wine With Wanda — who will be talking about all things Cabernet Franc at this year’s Food & Wine Classic in Aspen — views them as one of the most effective formats for preserving quality and structure over time.
“Sometimes, people mistakenly believe magnums are all about flash and not function,” says Mann. “There’s no denying the dramatic visual appeal of a large-format bottle, but many winemakers prefer to bottle their top wines in magnums because they are an ideal vessel for aging.” That’s especially true for wines that don’t always get top billing, like Cabernet Franc. The format gives them room to evolve — quietly, confidently — and show up with more structure when it counts.
What changes in a magnum?
A magnum holds 1.5 liters of wine — twice the standard bottle — but both allow in roughly the same amount of oxygen over time. This shift in ratio slows oxidation and extends the wine’s development. “Wines do age differently, and dare I say better, in magnums,” says Mann. “That slower oxidation allows the wine to develop complexity and depth over time.”
Producers often reserve this format for wines that benefit from aging — reds with acidity and tannin or complex whites made for more than just short-term drinking. Cabernet Franc fits neatly into that category. Similarly, Barolo, Pinot Noir, and structured styles of Chardonnay and Champagne are also notable examples.
Magnums aren’t just about preserving wine forever. They’re about allowing it the time to reach its full potential — especially if you’re opening something that might otherwise drink a little young.
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Not necessarily more inexpensive, but often smarter
There’s no cost advantage to buying magnums. “Magnums aren’t usually cheaper than buying standard bottles,” Mann notes. Still, they can offer value in other ways. They age more gracefully, serve about ten glasses — enough for a table of guests, and remove some of the guesswork around bottle timing. “If we’re focused on aging,” Mann adds, “magnums are ideal for wines with a structure that supports longevity.”
That applies to a wide range of wine styles, from Champagne and Verdicchio to age-worthy reds like Cabernet Sauvignon and Cab Franc. The slower evolution allows these wines more space to open up, particularly in vintages where the structure is there, but the fruit hasn’t fully softened. And in practical terms, bringing one magnum to the table is often easier — and more striking — than juggling two bottles.
Why the magnum format feels different
Magnums don’t just serve differently. They read differently. There’s a shift in tone when a magnum hits the table — not because it’s expensive, but because it feels intentional. “Magnums are fun,” Mann says. “They are instant conversation starters that captivate guests and add the right kind of drama to the drinking experience.”
They don’t have to be splurges either. Affordable Proseccos, pét-nats, and lighter reds are increasingly available in large format. The impact remains the same, even if the price doesn’t climb. And in a time when home dinners sometimes carry more weight than dining out, this format delivers a little extra without doing too much.
The case for buying magnums
Magnums aren’t just shelf pieces or party props. They’re tools for better aging, smarter serving, and a slightly more generous pour. If you’re holding a wine that’s not quite ready to drink — or looking to elevate something more casual — the format helps on both counts.
For varieties like Cabernet Franc that benefit from structure and patience, a magnum offers the right conditions. It’s not about making a splash. It’s about giving the wine time and giving the moment more space.