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Cat Birthday Party & Tree House

Snapshot

vs RRP
32% under
Per piece
4.1¢

Value per piece

cost per part at each reference

4.1¢lowest market value

about 56% under retail, which runs ~9.3¢ a piece

Reference

MSRP9.3¢
Used market4.1¢
New market6.4¢
Set Retiring soon · Dec 2026

Cat Birthday Party & Tree House

Reference
42666-1
Theme
Friends
Year
2025
Parts
321
UPC
673419402125
EAN
5702017783758

Cat Birthday Party & Tree House is a LEGO set from the LEGO Friends theme released in 2025. It is built from 321 pieces.

New avg$20.40Used avg$13.26MSRP$29.99

Avg. 3rd-party market prices via BrickPicker, not CollectORbuild seller prices

See full valuation & price history →Track its value free →
Value history$20.40▼ -$18.28 (-47.3%)all time
$19$26$33retail $29.99
Jul 4New · used (dashed)Jul 25

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Parts in this set (171)

View all parts →

A peek at the pile. See the full list, grouped by color, on the parts page.

Sticker Sheet for Set 42666-1Photo shows a different color. This lot is (Not Applicable).1×Animal, Cat, Kitten Sitting with Yellow Eyes, Dark Pink Tongue printPhoto shows a different color. This lot is Black.1×Bar 5L with Handle (Friction Ram)1×Equipment Candlestick1×Plate Round 1 x 1 with Hollow Stud and Horizontal Bar 1L1×String with End Studs 11L OverallPhoto shows a different color. This lot is Black.1×Hose Rigid 3mm D. 9L / 7.2cmPhoto shows a different color. This lot is Black.1×Brick Special 1 x 1 with Studs on 2 Sides1×Cupboard 2 x 3 x 2 with Hollow Studs1×Wedge Plate 2 x 41×Dish 2 x 2 Inverted [Radar]2×Plate Round Corner 6 x 62×Plate Round 1 x 2 Half Circle with Stud (Jumper)Photo shows a different color. This lot is Blue.1×Plate Special Round 2 x 2 with Center Stud (Jumper Plate)2×View all 171 →