Burgundy Ullage in CM: What Each Level Means

A 5cm ullage on a Burgundy is normal, good for age, or a reason to bid less. Which one it is depends on the bottle's decade and whose catalogue you are reading. Burgundy ullage is the distance from the base of the cork to the surface of the wine. It is measured in centimetres instead of named against a shoulder. WineBid considers 2cm or less "an excellent fill for any age and does not need to be mentioned". For wines 12 years and older, 3cm is "a perfectly normal fill" according to WineBid. If a wine is more than 20 years old, 4cm is "a normal fill" and "excellent for wines more than 35 years old". Christie's, quoted by Decanter, states that "ullage of up to 7cm is relatively normal in 30-year-old Burgundy". These levels are important because a low ullage can indicate "seepage and oxidation of the wine, and affect its value considerably" as WineBid notes. Read the centimetres against the decade before you read them against the estimate. A level that matches the decade costs you nothing. A level running two decades ahead of it is where the discount lives.

Why is Burgundy ullage measured in centimetres?

Burgundy ullage runs in centimetres because Burgundy bottles have a different shape from Bordeaux and Cabernet Sauvignon bottles. WineBid states that "Burgundy ullage has historically been measured in centimeters because Burgundy bottles are shaped differently than Bordeaux and Cabernet Sauvignon bottles". We further clarify that "The fill levels descriptions are different for Bordeaux and Burgundy wines due to the different shape of the bottles from those two regions". Decanter also notes that "Burgundy ullage is measured in centimetres, because of the bottle shape".

The measurement itself starts at the base of the cork. It does not start at the lip of the bottle or the top of the capsule. WineBid specifies that "Fill levels for Burgundy are measured by looking at the space between cork and wine". In a lot note, this reading appears as "u." WineBid uses "(u. 2x5cm)" to mean two bottles ullaged 5 centimetres. For a broader understanding of different fill levels, consult our guide to wine ullage levels explained. You can also explore the Burgundy producer atlas.

What cm level is normal for each age?

Index the reading to the wine's age. Then read across. The published bands line up like this.

Age in Years	Ullage Level	Assessment	Published by
Any age	2cm or less	Excellent fill, needs no mention	WineBid
12 years and older	3cm	Perfectly normal fill	WineBid
25 years or older	3cm	Excellent fill level	WineBid
20 years and older	4cm	Normal fill	WineBid
35 years and older	4cm	Excellent fill	WineBid
30 years and older	5cm	Not uncommon	WineBid
30 years old	Up to 7cm	Relatively normal	Christie's (quoted by Decanter)

A level that counts as "normal" or "excellent for age" points to good storage. The bottle is likely to be in good condition. You can use this information when assessing potential purchases. It also helps you decide when to open your own bottles. For specific producer guidance, you can also consult our cm-below-cork bands by decade for DRC Romanée-Conti and Domaine Leroy. For more insights on evaluating wine condition, explore our guide on how to buy wine at auction.

What causes ullage in bottled Burgundy?

Evaporation and diffusion primarily cause ullage. Ullage is the headspace of air between the wine and the top of the container. "As a cork is not a completely airtight sealant, some wine is lost through the process of evaporation and diffusion". As wine ages in the bottle, "the amount of ullage will continue to increase" unless the wine is opened, topped up, and recorked.

The evaporation of alcohol and water particles from the wine is sometimes referred to as the "angel's share" in barrels. In bottles, this process contributes to the increasing ullage. If wine sits on its side, in contact with the cork, the cork can also absorb some wine. Longer corks potentially absorb more wine. They thus create more ullage, as we describe. The transfer of oxygen from the outside environment to the wine in the bottle occurs not only through the stopper itself. It also happens significantly at the interface between the cork stopper and the glass bottleneck, as highlighted by a study by Chanut, Bellat, Gougeon, and Karbowiak (2023).

How does ullage affect the condition of your wine?

The amount of ullage can significantly affect the condition of your wine, primarily by indicating potential exposure to harmful levels of oxidation. "Generally the greater the amount of ullage, the more potential that the wine has been exposed to harmful levels of oxidation". Decanter's Matt Walls notes that "the fill level is low, it suggests that air has been seeping into the bottle, which would cause the wine to oxidise".

Oxidation can lead to various wine faults. The Australian Wine Research Institute (AWRI) describes oxidation sensory characteristics ranging from a "dulling of the aroma" to "cardboard", "straw", and "hay-like" aromas, and even "sherry-like" and "madeirised" in extreme cases. The AWRI also mentions "wet wool", "wet dog", or "varnish-like" aromas as possible in extreme cases.

Beyond oxidation, ullage levels can offer insight into the wine's storage history. Decanter's Julia Sewell explains that "low fill levels indicate poor storage conditions, namely high temperature or low humidity". Wines kept at ambient humidity levels and in temperatures between 10-15 °C (50-59 °F) will experience evaporation and diffusion at a slower rate. That leaves them with lower ullage levels. This makes ullage an important indicator for assessing the potential quality and value of mature wines. Auction houses and retailers "pay close attention to the ullage levels". Understanding these factors is crucial for fine wine investment.

How do storage conditions impact ullage and oxygen transfer?

Storage conditions play a critical role in the evolution of ullage and the rate of oxygen transfer into a bottled wine. A study by Chanut, Bellat, Gougeon, and Karbowiak (2023) investigated the oxygen barrier properties of microagglomerated cork-based stoppers over 24 months. That work used miniaturized bottle systems with model wine, mimicking various conservation conditions.

The study found that the oxygen diffusion coefficient of the cork stopper alone was "not modified" regardless of the storage conditions. Those conditions included temperature, storage position, and the presence of model wine. However, the presence of model wine significantly affected the total oxygen transfer. That total accounts for both transfer through the stopper and at the glass-cork interface. The total diffusion coefficient increased from an average initial value of 2.3 × 10⁻¹¹ m² s⁻¹ to 4.7 × 10⁻¹¹ m² s⁻¹ after the first three months of storage at 20°C. That temperature counts as ambient for bottles on shelves. This increase meant that the transfer at the glass-cork interface accounted for "nearly 70% of the total oxygen transfer".

Bottle position during storage may be vertical (cork in contact with the vapor phase) or horizontal (cork in contact with the liquid phase). Either way it "did not modify the oxygen transfer" through the bottleneck-cork system, according to Chanut, Bellat, Gougeon, and Karbowiak (2023). These observations held for all durations measured from 3 to 24 months at 20°C.

Temperature, however, had a strong impact on oxygen transfer. At a storage temperature of 20°C, the oxygen barrier properties of the bottleneck-cork system remained "unchanged over 24 months of aging". At 35°C, a temperature "easily reached during bottle shipping", the total oxygen transfer "did not increase significantly for up to 9 months". Beyond this duration, a "significant transfer at the glass-cork interface started to occur". At an even higher temperature of 50°C, this shift in oxygen transfer at the glass-cork interface "already occurs within the first 3 months of storage". That can potentially lead to "leakage" at the interface, as the study notes. This increased transfer at higher temperatures could be due to a "partial melting of the surface treatment agent" on the cork or a "modification of the mechanical properties of the cork".

Maintaining optimal storage conditions is crucial for minimizing ullage and preserving your wine, as Decanter suggests. That means a temperature of around 13-15°C and a humidity level of 70% or so. For guidance on protecting your collection, review our storage pillar. You can also use our landed-cost calculator to factor in storage costs when acquiring new wines. Stay informed about the market value of your Burgundy collection by checking our live fine wine market index.

Stay informed about the market value of your Burgundy collection. Get price alerts on your watchlist to track changes and make timely decisions.