The most commonly recognized form of antique clock, is typically referred to as a Grandfather clock. Known among collectors as "tall case clocks", these early American clocks range in size, but are normally around eight feet tall. Considered a luxury item at their time of manufacture, the cases are often constructed of vibrant, high quality hardwoods and can feature elaborate inlays, carving and paint decorations. Grandfather clocks were abundantly produced throughout the country and appear with great regional variety. The form began to dwindle in popularity by the 1830's, and was replaced by less expensive manufactured examples. Antique tall case clocks can be found by hundreds of different early American clock makers.

Developed at the beginning of the 19th Century by renowned clock maker Simon Willard in Roxbury, Massachusetts. He called it his "Willard's Improved Patent Time Piece". Known today as Banjo clocks, these elegant wall clocks are prized by collectors. This reliable and affordable style quickly replaced the tall clock in many local regions and significantly influenced American clock making. Banjo clocks have never gone out of favor and numerous examples were produced into the 20th Century. The form is prone to restoration, especially to their glass "eglomise" panels and very few early examples survive in original condition. Several important 19th century clock makers produced these patent time pieces. Some prolific makers include Lemuel Curtis of Concord, Ma, Elnathan Taber of Roxbury, Ma, and William Cummens of Roxbury, Ma.

Dwarf clocks were made to appear as a tall case clock, but measuring around four feet tall, they were scaled down and slightly more affordable than a full size grandfather clock.   This style was previously referred to as a Grandmother clock. It was produced primarily in Southeastern Massachusetts, particularly in Hingham and Hanover, during the first quarter of the 19th Century. Diminutive dwarf clock cases appear in distinctive varieties, including both mahogany and paint decorated pine examples. They were produced as a more affordable alternative to a full size tall case clock. Clockmakers Joshua Wilder of Hingham, Ma and his apprentice Reuben Tower, who worked in Hingham, Plymouth and Kingston, Ma were the most prolific dwarf clock makers.

Bracket clocks are spring driven shelf clock, produced throughout the 18th and 19th Centuries. A form produced primarily in England. Nearly all examples that bear American clockmaker's names were imported from Britain. It was common practice for American clock makers to order English bracket clocks, signed with their own names in place of the actual maker. American bracket clocks are quite rare and are prized by collectors. These clocks represent another very popular form that continued to be reproduced through the 20th Century.

Commonly referred to as the "Massachusetts Shelf Clock" or the "Mass. shelf clock", These clocks were most fashionable during the first third of the 19th Century. Often made by the Willards in Roxbury (Boston), Ma., they commonly appear in two distinct configurations. The earlier variation has a wooden front and a slightly kidney shaped dial. Collectors refer to these as "kidney dial Mass. shelf clocks". The later form of Massachusetts shelf clock, called the "dish dial"  features a round dial with reverse-painted glass panels (eglomise). Rare early examples such as those made by clockmakers David Wood and Daniel Balch of Newburyport, Ma. can be found with tombstone shaped dials, some made of brass.

Grafton Wall clocks were sometimes called Willard experimental clocks or Willard timepieces. These small clocks were usually made in Grafton, Massachusetts, although some were made in Roxbury, Ma.  They were produced during the last quarter of the 18th Century. They are great rarities that were developed by Simon Willard and his brother Aaron Willard in an attempt to produce a small wall clock. These Willard time pieces appear with brass dials and often have a passing strike. Willard thirty hour wall clocks are among the rarest of all important American clocks.

The American version of the tavern clock was produced during the first third of the 19th Century. The form was developed and popularized in England, but did not have the same success in America, subsequently examples from this period are relatively rare. The majority of tavern clocks were manufactured in New England, primarily in Boston. Joseph Nye Dunning of Burlington, Vt. and Abel Stowell of Charlestown, Ma were makers of Tavern clocks. In the late 19th Century, similar production examples were introduced in the form of the "School House Clock". The values of these later clocks are significantly lower than early examples.

Mirror clocks are an attractive design that features a split column frame and a mirror in the lower tablet. Often called "New Hampshire Mirror clocks", this popular form was primarily produced in that state during the 1820's & 30's. Due to their fragile nature, mirror clocks are another form that is prone to have restoration to the glasses, with few examples surviving in original condition. Examples continued to be produced in New York and Connecticut until the middle part of the 19th Century.