27 CFR 4.21 contains the standards of identity for wine — the definitions that determine what a wine may, and must, call itself. It anchors Subpart C of Part 4, and it feeds directly into the labeling rules: under § 4.32(a)(2) every wine label must state a class, type, or other designation on the brand label, and under § 4.34 that designation must conform to the § 4.21 standard. A wine that meets a standard must be designated accordingly; a wine that meets no standard must instead carry a truthful and adequate statement of composition. TTB checks the designation against the standards during COLA review.

The Class System at a Glance

Section 4.21 defines the following classes. (Class 4, formerly citrus wine, is now reserved — citrus wines are handled within the fruit wine class, which expressly permits a "citrus wine" designation.)

Class 1: Grape Wine — Table and Dessert

Grape wine (§ 4.21(a)) is wine produced by the normal alcoholic fermentation of the juice of sound, ripe grapes, with only the additions and cellar treatments authorized for natural wine under the Internal Revenue Code (26 U.S.C. 5382–5383). The standard caps volatile acidity at 0.14 g/100 mL for red wine and 0.12 g/100 mL for other grape wine, and permits color designations ("red," "pink (or rose)," "amber," "white") plus "natural" for wine with no added brandy or alcohol.

The alcohol line that drives the rest of the label sits here: table wine is grape wine at not more than 14 percent alcohol by volume (also designable as "light wine," "red table wine," and similar), while dessert wine runs over 14 up to 24 percent. Within dessert wine, named types carry minimum strengths derived in part from added grape brandy or alcohol: sherry requires at least 17 percent ABV, while angelica, madeira, muscatel, and port each require at least 18 percent; versions above 14 percent but below those thresholds must be designated "light sherry," "light port," and so on. These boundaries interlock with the § 4.36 rule that an alcohol content statement may never misstate the wine's class.

Class 2: Sparkling Grape Wine — Champagne vs. Charmat

Sparkling grape wine (§ 4.21(b)) is grape wine made effervescent with carbon dioxide resulting solely from fermentation within a closed container, tank, or bottle. Two production methods matter for labeling:

• Champagne is a type of sparkling light wine deriving its effervescence solely from secondary fermentation within glass containers of not greater than one gallon capacity (the traditional method), with the taste, aroma, and characteristics attributed to champagne from the Champagne district of France

• Sparkling wine with champagne character made by other methods — such as the charmat (bulk) process in large tanks — may not be labeled simply "champagne." It may, in addition to the mandatory class designation "sparkling wine," be further designated "champagne style," "champagne type," or "American (or New York State, Napa Valley, etc.) champagne" accompanied by a qualifier such as "bulk process," "fermented outside the bottle," or "not bottle fermented." "Charmat method" or "charmat process" may appear as additional information

TTB evaluates these labels as a whole for legibility and clarity — type size, contrast, and placement of the qualifying terms all count. Note that longstanding trade agreement commitments restrict "champagne" and other semi-generic names to grandfathered uses, so new brand labels generally use "sparkling wine" outright. The class also includes crackling wine (petillant, frizzante) — less effervescent sparkling wine, which must be designated "crackling wine — bulk process" when secondary fermentation occurs in containers over one gallon.

Class 3: Carbonated Grape Wine

Carbonated grape wine (§ 4.21(c)) is grape wine made effervescent with carbon dioxide other than that resulting solely from secondary fermentation in a closed container. Injected CO2 means the wine is "carbonated wine," never "sparkling wine" — the class designation itself discloses the production method.

Classes 5 and 6: Fruit Wine and Other Agricultural Products

Fruit wine (§ 4.21(e)) parallels the grape wine standard for fruit other than grapes: normal fermentation of sound, ripe fruit, IRC amelioration limits, and the same table (≤14%) and dessert (14–24%) split. Wine made wholly from one fruit is designated by that fruit ("peach wine," "blackberry wine"); blends take "fruit wine" or "berry wine" plus a statement of composition; wines wholly from citrus fruits may be designated "citrus wine." Wines wholly from apples or pears may be designated "cider" and "perry" — and must be, if lacking vinous taste and character. Sparkling and carbonated variants must say so.

Wine from other agricultural products (§ 4.21(f)) covers everything fermentable that is not grape, citrus, or fruit — with strict limits on added water, sugar, acidity, and solids. Named types include raisin wine and sake; otherwise the wine is designated by its source ("honey wine") or as "wine" plus a statement of composition.

Classes 7, 8, and 9: Aperitif, Imitation and Substandard, Retsina

Aperitif wine (§ 4.21(g)) must reach at least 15 percent ABV, be compounded from grape wine with added brandy or alcohol, and be flavored with herbs and other natural aromatic flavoring materials. Vermouth is a type of aperitif wine with vermouth's characteristic taste and aroma, and must be so designated.

Class 8 (§ 4.21(h)) is the penalty box. "Imitation wine" — including wine containing synthetic materials, wine made from water and pressing residue, or wine whose character comes from unauthorized treatments — must carry the word "imitation" in its designation. "Substandard" or "other than standard" wine — including wine exceeding the volatile acidity maximums or lacking the composition and clean vinous character of normal wine of its standard — must carry those words. Finally, retsina wine (§ 4.21(i)) is grape table wine fermented or flavored with resin.

What Determines the Designation on the Label

The class designation is determined by composition and production method, not marketing intent. Under § 4.34, the label must state the class per § 4.21 — or, for still grape wine, may substitute a varietal, semi-generic, or geographic distinctive designation — and a wine defined by no standard must carry a statement of composition instead. The practical workflow: identify the source material (grape, fruit, other), the alcohol content bracket, the effervescence method, and any added spirits or flavoring, and the class falls out of § 4.21. Products like flavored wine specialties that fall outside every class are designated by statement of composition, which triggers its own conjunction and type size rules.

How Truli Helps with Standards of Identity Compliance

• Class verification: Truli cross-checks the label's class and type designation against the § 4.21 standard implied by your product's composition, alcohol content, and production method

• Boundary flags: Truli catches designations that conflict with the stated alcohol content — a "table wine" at 14.8%, a "sherry" labeled 16% — before they reach TTB

• Sparkling terminology checks: Truli screens champagne-style labels for the required qualifiers and the mandatory "sparkling wine" class designation

• Statement of composition support: for products outside the defined classes, Truli reviews the statement of composition for adequacy and conjunction with the brand name

Related Regulations

• 27 CFR Part 4 — TTB Wine Labeling Requirements — The full wine labeling framework this section belongs to

• 27 CFR 4.34 — Wine Class and Type Designation — How the § 4.21 class must be stated on the brand label

• 27 CFR 4.32 — Mandatory Wine Label Information — Where the designation fits among the required label elements

• Wine Appellations, Varietals, and Vintage Dates — The varietal and origin designations that can substitute for a class statement

• 27 CFR 4.39 — Prohibited Practices on Wine Labels — Including the ban on simulating a designation the wine is not entitled to bear

Frequently Asked Questions

Can I label my tank-fermented sparkling wine "champagne"?
Not as a standalone designation. Champagne under § 4.21(b)(2) requires secondary fermentation in glass containers of one gallon or less. A charmat-process wine must be designated "sparkling wine," and may add a qualified term such as "American champagne — bulk process" only where the grandfathered semi-generic pathway applies; most new brands simply use "sparkling wine."

What class is my 15.5% ABV zinfandel?
Dessert wine. Grape wine over 14 percent and up to 24 percent ABV falls in the dessert wine category of Class 1, regardless of sweetness or style, and its alcohol content statement must reflect that class under § 4.36(c). "Table wine" and the "table"/"light" designation option are unavailable above 14 percent.

My cider is made entirely from apples at 8% ABV. How is it designated?
As "cider" (fruit wine, Class 5) if it is at least 7 percent ABV and therefore under Part 4 at all. Fruit wine wholly from apples may be designated "cider" — and must be, if it lacks vinous taste and characteristics. Below 7 percent ABV, the product leaves Part 4 for FDA food labeling rules.

A note from Truli: Truli is not a law firm, and this article does not constitute or contain legal advice or create an attorney-client relationship. When determining your obligations and compliance with respect to relevant laws and regulations, you should consult a licensed attorney.

Last updated: August 2026. Reflects 27 CFR 4.21 as of August 2026. Truli monitors TTB rulemaking and enforcement. Book a demo to see how.