Is lego birthday party supplies profitable to sell on Amazon United States?

The niche generates $862K/yr across 57 tracked products. 7 of 19 products launched in the last 360 days are still selling. 90-day search growth is -4.7%. Flapen's verdict: Worth a look (65/100).

How competitive is the lego birthday party supplies niche?

44 brands and 130 sellers compete. The top 5 products take 27% of clicks and top 5 brands hold 35% of demand.

What do buyers complain about in lego birthday party supplies?

Top complaints mined from reviews: Size-Overall, Quality-Overall, Value For Money. The return rate is 2.0%.

When does demand for lego birthday party supplies peak?

Demand peaks in Jan; the busiest month runs 1.9× the quietest.

What does it cost to enter the lego birthday party supplies niche?

Listings span $4.37–$53.36; the average listing price is $17.38 (sweet spot $15–$100). The average incumbent carries 375 reviews — the moat a new listing must climb.

lego birthday party supplies

Worth a look

Shows no brand lock-in (top 5 brands take 35% of clicks), but a failed launch gate (market size, growth, or returns) keeps it on the watch list.

Brand share

Incredible35%

top-5 brand share — no brand owns this niche

Competition

Great27%

top-5 click share — an open shelf

Review moat

Great375.28

avg incumbent reviews — the moat a new listing must climb

Avg price

Great$17.38

avg listing price — sweet spot $15–$100

Price range

Great$4.37–$53.36

cheapest to priciest tracked listing — scored on the share inside $15–$100

Market size

Great$862K

$862K/yr · 1.2M searches

Returns

Great2.0%

return rate — above 5% kills the launch gate

Conversion

Good4.3%

search→purchase rate — share of searches ending in a sale

Quality gap

Bad4.6★

avg incumbent rating — lower means beatable quality

Growth

Bad-4.7%

90-day search growth — must beat 0% to launch

Signals No Dominant Brand

According to Flapen's Amazon United States niche tracking, lego birthday party supplies is a $862K/yr Amazon United States market (1.2M searches/yr). The top 5 brands hold 35% of demand. Demand peaks in Jan. Verdict: Worth a look — 65/100.

Data updated Jul 23, 2026 · scored weekly · How we score niches

lego birthday party supplies market data

Units sold / yr: 40K–50K; avg 500–750/product
Revenue / yr: $695K–$869K; units × avg price
Conversion rate: 4.3%
Avg BSR: #1,234
Page quality: 0%
Prime: 98%
Sponsored: 89%
Out of stock: 1.2%
Avg brand age: 31 months
Avg seller age: 151 days

Competition & brand share

Clicks spread well past the top 5 (27% combined) — an open shelf where new products get seen.

Brands

44 falling

Sellers

130

Top-5 brand share

35%

Top 20: 75%

Top-5 click share

27%

Top 20: 63%

Open market

61%

LEGO11%
QIYANPAX10%
PHD CAKE6%
LINHAXM5%
Kinovo4%
Rossesay4%

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — -4.7% search growth over the last 90 days.

Peak months: Jan · busiest ÷ quietest = 1.9×

Open Trend

Top lego birthday party supplies search terms

lego birthday decorations303K/yr +2.5%3.1% conv.
lego party decorations164K/yr -4.0%3.0% conv.
lego birthday121K/yr -2.4%2.3% conv.
lego party118K/yr -8.5%1.6% conv.
lego decorations69K/yr +12.7%1.1% conv.
lego themed birthday party41K/yr +4.5%1.9% conv.
lego party supplies48K/yr -7.3%2.7% conv.
lego birthday party30K/yr +6.7%1.9% conv.
lego decorations for birthday party29K/yr +4.6%2.7% conv.
birthday lego30K/yr -10.5%2.1% conv.

All search terms

Top lego birthday party supplies products on Amazon

Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.

Beatable (≤4.3★) Contested Strong incumbent (>4.7★)

All 24 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

173 PCS Building Block Birthday Party Decorations - Plates Napkins Cups Cutlery Cake & Cupcake Toppers Banner Hanging Swirls Tablecloth Balloons for Birthday Party Serves 20

QIYANPAX$23.564.7★422 rev

PHD CAKE Number 7 Building Block Birthday Cake Candle Numeral Birthday Candles

PHD CAKE$5.954.8★320 rev

LEGO Birthday Party Cake - Building Toy for Boys & Girls Ages 7+ - Birthday Decoration with 10 Candle Accessories - Craft for Kids - 40815

LEGO$14.865.0★35 rev

197 Pcs Building Blocks Birthday Paper Plates Tableware Set (Serves 24) Colorful Blocks Supplies Include Banner Pendant Plates Napkins Cups Forks Knives Tablecloth Topper Balloons For Kids Party

Kinovo$27.404.6★48 rev

Rossesay Building Block Number 0-9 Birthday Cake Candle Numeral Birthday Sparkler Candles for Building Block Cake Topper for Party Decorations Supplies(Number 5)

Rossesay$6.884.5★845 rev

Newest

by launch date

LEGO Birthday Party Cake - Building Toy for Boys & Girls Ages 7+ - Birthday Decoration with 10 Candle Accessories - Craft for Kids - 40815

LEGO$14.8635 rev

1mo ago

NKPDAXM Building Block Birthday Decorations Colorful Building Block Plates Napkins Cups Tablecloth Banner Hanging Swirls Balloons Honeycomb Centerpieces for Block Birthday Party Serves 24

NKPDAXM$20.8659 rev

4mo ago

224Pcs Building Block Birthday Decorations ALL-IN-1 Serves 26

Haiyumaoyi$25.1212 rev

4mo ago

198Pcs Building Block Birthday Party Decorations with Plates Napkins Cups Banner Backdrop Tablecloth Balloons Cake Toppers Honeycombs for Boys Kids Birthday Party Supplies Serve 24 Guests

Gupesxu$26.3310 rev

5mo ago

Building Block Birthday Party Supplies Colorful Building Block Plates Napkins Cups Tablecloth Banner Hanging Swirls Balloons Honeycomb Centerpieces for Birthday Party Serves 24

LINHAXM$19.859 rev

6mo ago

What buyers say about lego birthday party supplies

What buyers praise and complain about, mined from review topics.

What buyers love

Quality-Overall13%

“The variety is really good”

Color12%

“The colors are vibrant”

Value For Money11%

“Good for price”

Fun/Entertainment Experience10%

“Hours of Fun”

Size-Overall5%

“it fit our needs”

Advertised Vs Actual Product5%

“As advertised”

Gifting Purpose5%

“Its a gift”

Design-Overall5%

“the animal designs are cute”

Assembly/Installation4%

“Very easy to put together”

Ease Of Use4%

“Easy to use”

What buyers complain about

Size-Overall14%

“Very small”

Quality-Overall7%

“Bad quality”

Value For Money6%

“What a huge waste of money”

Assembly/Installation5%

“Instructions are hard”

Inflation/Deflation4%

“The balloon would not stay inflated”

Instructions/User Manual/Troubleshooting4%

“Instructions are not the greatest”

Strength3%

“That said, they dont fit together quite as smoothly as name-brand blocks, and a few of the animal designs arent perfectly balanced, so they may not always stand on their own”

Functionality-Overall2%

“of course that didnt work”

Advertised Vs Actual Product2%

“Some Decorations are Different”

Thickness2%

“They were really thick”

Top return reasons

Size-Overall34%

Value For Money15%

Advertised Vs Actual Product11%

Quality-Overall9%

Defective Material/Parts5%

Material Quality4%

Color4%

Thin3%

Inflation/Deflation2%

Design-Overall1%

Common questions

Is lego birthday party supplies profitable to sell on Amazon United States?: The niche generates $862K/yr across 57 tracked products. 7 of 19 products launched in the last 360 days are still selling. 90-day search growth is -4.7%. Flapen's verdict: Worth a look (65/100).
How competitive is the lego birthday party supplies niche?: 44 brands and 130 sellers compete. The top 5 products take 27% of clicks and top 5 brands hold 35% of demand.
What do buyers complain about in lego birthday party supplies?: Top complaints mined from reviews: Size-Overall, Quality-Overall, Value For Money. The return rate is 2.0%.
When does demand for lego birthday party supplies peak?: Demand peaks in Jan; the busiest month runs 1.9× the quietest.
What does it cost to enter the lego birthday party supplies niche?: Listings span $4.37–$53.36; the average listing price is $17.38 (sweet spot $15–$100). The average incumbent carries 375 reviews — the moat a new listing must climb.