In 2021, LEGO released 14 Seasonal sets across 6 subthemes, all of these sets have been retired. Subthemes for that year included Chinese New Year, Chinese Traditional Festivals, Christmas, Easter, Halloween, and Valentines Day. For that year, the total price of all retail sets cost $325, today those sets are valued around $666, a growth of 105%.
Most valuable 2021 LEGO Seasonal set
40489 Mr. and Mrs. Claus' Living Room $251.40
Highest growth 2021 Seasonal set
40493 Spider & Haunted House +166.27%
Largest 2021 LEGO Seasonal set
80107 Spring Lantern Festival 1,793 pieces
Most owned 2021 Seasonal set
40499 Santa's Sleigh
14 sets

30579 Easter Chick Egg

Theme / Subtheme Seasonal / Easter
Year 2021
Pieces 52
Availability Retired
30579 LEGO Easter Chick Egg
Retail $4.99
Value $11.97
Growth  +139.9%
Annual growth 12.3%

40417 Year of the Ox

Theme / Subtheme Seasonal / Chinese New Year
Year 2021
Pieces 168
Availability Retired
40417 LEGO Year of the Ox
promotional
Value $8.41
Annual growth 26.5%

40449 Easter Bunny's Carrot House

Theme Seasonal
Year 2021
Pieces 232
Availability Retired
40449 LEGO Easter Bunny's Carrot House
promotional
Value $16.52
Annual growth 37.4%

40462 Valentine's Brown Bear

Theme / Subtheme Seasonal / Valentine's Day
Year 2021
Pieces 245
Availability Retired
40462 LEGO Valentine's Day Valentine's Brown Bear
Retail $14.99
Value $22.71
Growth  +51.5%
Annual growth 5.9%

40463 Easter Bunny

Theme / Subtheme Seasonal / Easter
Year 2021
Pieces 293
Availability Retired
40463 LEGO Easter Bunny
Retail $14.99
Value $19.29
Growth  +28.7%
Annual growth 7.8%

40484 Santa's Front Yard

Theme / Subtheme Seasonal / Christmas
Year 2021
Pieces / Minifigs 317 / 1
Availability Retired
40484 LEGO Christmas Santa's Front Yard
promotional
Value $19.98
Annual growth 39.3%

40489 Mr. and Mrs. Claus' Living Room

Theme / Subtheme Seasonal / Christmas
Year 2021
Pieces / Minifigs 344 / 2
Availability Retired
40489 LEGO Christmas Mr. and Mrs. Claus' Living Room
promotional
Value $251.40
Annual growth 30.3%

40493 Spider & Haunted House

Theme / Subtheme Seasonal / Halloween
Year 2021
Pieces 132
Availability Retired
40493 LEGO Halloween Spider & Haunted House
Retail $9.99
Value $26.60
Growth  +166.3%
Annual growth 11.2%

40494 Polar Bear & Gift Pack

Theme / Subtheme Seasonal / Christmas
Year 2021
Pieces 142
Availability Retired
40494 LEGO Christmas Polar Bear & Gift Pack
Retail $9.99
Value $19.95
Growth  +99.7%
Annual growth 9.6%

40497 Halloween Owl

Theme / Subtheme Seasonal / Halloween
Year 2021
Pieces 228
Availability Retired
40497 LEGO Halloween Owl
Retail $14.99
Value $25.91
Growth  +72.8%
Annual growth 9.1%

40498 Penguin

Theme / Subtheme Seasonal / Christmas
Year 2021
Pieces 244
Availability Retired
40498 LEGO Christmas Penguin
Retail $14.99
Value $19.71
Growth  +31.5%
Annual growth 6.0%

40499 Santa's Sleigh

Theme / Subtheme Seasonal / Christmas
Year 2021
Pieces / Minifigs 343 / 1
Availability Retired
40499 LEGO Christmas Santa's Sleigh
Retail $39.99
Value $35.70

80106 Story of Nian

Theme / Subtheme Seasonal / Chinese Traditional Festivals
Year 2021
Pieces / Minifigs 1,067 / 6
Availability Retired
80106 LEGO Chinese Traditional Festivals Story of Nian
Retail $79.99
Value $68.27

80107 Spring Lantern Festival

Theme / Subtheme Seasonal / Chinese Traditional Festivals
Year 2021
Pieces / Minifigs 1,793 / 8
Availability Retired
80107 LEGO Chinese Traditional Festivals Spring Lantern Festival
Retail $119.99
Value $119.72