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Christmas Sale & Event Poster Designs

Christmas poster designs for shops, market stalls and event organisers who need seasonal artwork fast - and for the people selling through the season. The collection runs three tracks in one place: atmospheric pieces (candlelit tables, snowy forests, paper-cut trees), promotional layouts where the price plate, discount badge and countdown panel are already built into the composition, and event artwork for parties, markets, church services and year-end concerts. Palettes stay controlled - deep evergreen, oxblood, warm white - with gold reserved for the offer rather than the decoration. Every design is composed for a real placement: story, feed post, marketplace thumbnail, printable poster or wide web banner, so the crop and headline weight already match where it will run.

Format
Occasion
Product
Christmas greeting poster, vertical, macro ornament still life. [Colors] cherry red #C21F2C to soft crimson #8E1B24 gradient, metallic pearl #EFE7DA and gold #D6A94F baubles, muted teal #3E6F63 at the base. [Layout] baubles suspended on red ribbons from a garland across the top, generous empty red space in the middle holding the wordmark, a snow-capped candy-red capsule label below, caption and QR at the bottom. [Typography] high-contrast serif italic for the greeting, light spaced sans for the closing wish. [Subject] striped and floral-etched glass ornaments with satin bows, gold filigree stars dangling, pine sprigs at the very top. [Lighting & mood] warm bokeh glow, festive abundance, shallow focus. [Details] crisp specular highlights on glass, soft snow specks, delicate metal chain. Text: "MERRY CHRISTMAS", "WISHES COME TRUE".Professional Christmas promotional poster, vertical, glossy 3D type over a deep red field. [Colors] Lacquer red gradient (#A8121B to #7C0A11), champagne gold (#E7C27A), candy green and white accents, warm bokeh haze. [Layout] Logo centred at the top, an extruded gold headline, a dashed-outline coupon badge below it, a floating gift cluster arranged in a triangle in the middle, then a promotion line and two stacked offer rows, each with a rounded label chip on the left and small print on the right, plus a code square bottom-right. [Typography] Chunky beveled gold display face with a dark extrusion for the headline, white rounded sans for badges and offer copy. [Subject] Suspended gifts: a white box with a red bow, striped and red parcels, a gingerbread man in a Santa hat, green and gold baubles, a small fir, a gold star and a striped candy cane, each casting a soft shadow. [Lighting & mood] Festive retail spotlight, glossy highlights, urgent cheer. [Details] Sparkle ticks, blurred ornament bokeh, thin gold rule above the offers. Text: "WARM WINTER GIFTS", "50% OFF", "FREE GIFT".Christmas greeting poster, vertical, plush 3D character scene with a toy-photography feel. [Colors] Bright sky blue #5CB7E8, brick terracotta #C4704E, cherry red #D42B2B hat and suit, off-white fleece #FBF3E8, snow blue #DFEAF2, fir green #2F7A4E, gold and magenta baubles. [Layout] A wide arched chimney mouth opens through the middle of the frame; the upper band carries oversized white caps; a small script signature and subtitle close the bottom over a snowbank; a miniature village strip runs along the base. [Typography] Fat rounded white sans caps with tight leading, a delicate script word beneath, fine tracked micro text. [Subject] A plush Santa, all fuzz and fluff, leans out of the round brick chimney with both mittens on the rim, peeking over the edge; below, a small decorated tree with coloured bulbs, a felt reindeer, a tiny snowman and ribboned gift boxes crowd the snow. [Lighting & mood] Crisp daylight, high-key highlights, cuddly and humorous. [Details] Individual fibres catching light, brick texture, drifting flakes, painted snow caps on every surface. Text: "MERRY CHRISTMAS".Professional Christmas greeting poster, vertical, storybook gouache illustration. [Colors] midnight indigo #1E2A63 fading to periwinkle #6C7FC4, moonlit lavender #C3CCE8 snow, warm amber #E39A3C window light, deep pine #2C5B4A. [Layout] wide painterly script wordmark across the top, a cloud-framed oval opening into a snowy valley, cabin at left, sleigh at right, caption block and QR code at the bottom. [Typography] fluid brush-script headline, small condensed sans for the closing line and date. [Subject] Santa standing in a red sleigh piled with wrapped boxes, a reindeer trotting ahead in reins, snow-laden cabin, full moon, distant peaks. [Lighting & mood] cool moonlit night with warm window glow, calm and magical. [Details] visible brush texture, soft falling snow, reflected light on a small pond. Text: "MERRY CHRISTMAS", "DEC 25".Professional Christmas greeting poster, vertical, 3D voxel toy-render illustration. [Colors] Turquoise sky (#28A79E), snowy white (#F4F8F6), candy red and forest green blocks, tangerine globe base (#E07A3C), cocoa wood cabin. [Layout] Logo lockup and date share the top corners, a two-line rounded script headline spans the upper width, the giant glass globe sits centred on a snow mound, two tiny figures stand in the foreground left and right, and one bilingual-style line plus a code square close the bottom. [Typography] Soft rounded script, white with a faint shadow; a bold slab-sans for the closing line in deep teal. [Subject] Inside the sphere a blocky Santa waves from a red sleigh pulled by a cubist reindeer, surrounded by angular firs and stacked parcels; outside, two elf characters hold a candy cane, with a wrapped gift and a timber cabin at the edges. [Lighting & mood] Bright even daylight with cool shadows, cheerful and game-like. [Details] Faceted cube edges, translucent glass rim, chunky snow caps, light snowfall. Text: "MERRY CHRISTMAS", "YOUR GIFT HAS ARRIVED".Christmas greeting poster, vertical, needle-felt 3D craft scene on a plain crimson field. [Colors] Deep red #B8232A backdrop, woolly forest #2E6B4C tree, oat cream #F1E4CF fleece, clay red #C0392B suit, brass #C9A227 ornaments, sand beige #D9C6A5 kraft paper. [Layout] The type block sits in the upper-left quadrant with the date split left and right of a small script script line; the tree fills the right column from the footer upward; the Santa figure occupies the lower-left; gifts are grounded along the bottom edge. [Typography] Elegant high-contrast script for the greeting, a bracketed plain sans line under it, tiny numerals for the date. [Subject] A jolly felted Santa with a huge curled moustache and stitched smile grips a small ribboned present; a tall fir beside him is built from layered green felt scallops hung with matte red, gold and olive baubles and topped with a felt star; a rustic sleigh and two kraft-paper parcels sit in the drift. [Lighting & mood] Soft even tabletop light, tactile cosiness, handmade warmth. [Details] Visible wool fibre fuzz, embroidery seams, embroidered snowflakes in the corners. Text: "MERRY CHRISTMAS", "2025 · 12.25".Professional Christmas greeting poster, vertical, sculptural still-life render. [Colors] maroon #6E1420 to dusky rose #C56A5B gradient sky, deep pine #14624A book covers, ivory #F5EFE2 pages, brushed gold #D8A94E accents. [Layout] headline centred at the top, a stacked tower of books shaped like a Christmas tree occupying the middle, small parcels scattered on the snow at the base, a caption line and QR block at the bottom. [Typography] italic script for the sub-line, ultra-bold white sans for the main greeting, thin handwritten flourish beneath. [Subject] hardcover books fanned into three tiers with wavy cover art, gold star topper, ribbon-tied gift boxes, pencils and baubles tucked between volumes, miniature pines in misty background. [Lighting & mood] warm rim light, soft snow haze, hopeful studious atmosphere. [Details] visible paper edges, subtle snow drift, gentle depth of field. Text: "MERRY CHRISTMAS".Professional Christmas greeting poster, vertical, 3D clay-style rendered still life. [Colors] Oxblood walls (#6E1B1A), burnt orange floor and gift wrap (#C0502A), lacquer green tree (#7FA33C), polished brass (#D8A24E), warm peach arch (#E0A479). [Layout] Date in the top-right corner, a fat gold script headline wrapping the upper third, a tall arched niche behind the set, and a dense gift-and-tree tableau filling the lower two thirds with a spiral staircase of presents at the right. [Typography] Bulbous hand-lettered script with a metallic gold bevel and soft shadow; small serif caps for the date. [Subject] A smooth green cone tree banded by three gold rings threaded with tiny bells, a snow globe with a snowman on a red plinth, ribboned boxes in stacked tiers, a red stocking and a miniature green tree cluster. [Lighting & mood] Warm interior spotlight, glossy plastic highlights, cosy and toy-like. [Details] Rounded soft-body edges, floor reflections, a slim phone-strip of dots top-left. Text: "MERRY CHRISTMAS", "DEC 25".Christmas greeting poster, vertical, gradient light-beam minimal type composition. [Colors] Saturated vermilion #E8402F at the top melting into coral pink #F58A7C and shell white #FCEFE6 at the base, with a gold beam #F7C86A, warm red lettering #D8281F and a whisper of champagne #EFD8B0. [Layout] A wide triangle of golden light rises from a soft glow at the base to a star near the top, acting as the tree silhouette; the greeting sits high above it, a date block and short blessing flank the apex, and a band of outlined brush lettering anchors the bottom above the contact line. [Typography] Heavy brush-drawn caps with hairline double-stroke outlines for the main title, a small warm script beneath it, fine condensed roman for the date. [Subject] The tree exists only as a diffused gold gradient triangle with a star at its tip, crossed by two thin white orbital lines scattered with small white stars, with a white reindeer leaping at the right shoulder and a few sugar-dust specks floating inside the beam. [Lighting & mood] Dreamy backlit haze, gently rising warmth. [Details] Soft dither grain, oversized ghosted wordmark behind the lettering. Text: "MERRY CHRISTMAS", "12/25".Professional Christmas stream-overlay kit, vertical, knit textile design. [Colors] pine #1F6B45 and bottle green #14513A, chalky white #F7F4EC knit stitches, tomato red #C8352F accents, oatmeal #E8DCC6 gingerbread. [Layout] wide knitted banner across the top holding the headline, a large clean white product window in the middle, a matching knitted banner across the bottom, small stacked coupon cards floating at right. [Typography] rounded heavy sans in white for the header, small red badge labels, tidy coupon numerals. [Subject] hand-drawn Santa head peeking at the top-left corner, gingerbread man and reindeer at the bottom corners, a shoe product in the middle, star topper above a coupon stack. [Lighting & mood] soft flat studio light, cozy handcrafted warmth, e-commerce ready. [Details] visible cable-knit texture, snowflake stitches, stitched borders, candy-cane trim. Text: "MERRY & WARM", "40% OFF".Professional Christmas greeting poster, vertical, light-painting line-art composition on a flat colour field. [Colors] Warm crimson gradient (#C41A22 centre to #8E0C12 edges), luminous ivory-gold light (#FFF3CF), faint darker red ghost script, white sparkle dust. [Layout] A garland of star lights arcs across the very top, the greeting sits centred in the upper third over a ghosted script, a tall spiral light tree stands in the middle, one short two-line wish sits below it, and a code square is bottom-centred. [Typography] Bold serif greeting with wide tracking, translucent italic script layered behind as texture, small light sans for the wish. [Subject] A tree drawn entirely from a continuous glowing ribbon that spirals into a cone, topped with a five-point star, with a loose elliptical ring resting at its base. [Lighting & mood] Self-illuminated on darkness, cinematic bloom, serene. [Details] Fine star dots, drifting snow particles, soft red nebula haze behind the tree. Text: "MERRY CHRISTMAS".Christmas beauty campaign poster, vertical, photographic still life with studio lighting. [Colors] Deep spruce #123A2E backdrop fading to a bokeh cityscape of amber #F2B15C windows, sage green #6E8F5E gift boxes, rose-gold metal #C9946F jars, cream candle #F6E7C8. [Layout] A headline block sits top-left over a narrow caption; the date range stacks at top-right with a thin rule; the hero products form a low pyramid across the lower half; a garland of coloured bulbs and a felt fir slice the middle ground. [Typography] Bold condensed sans caps for the headline, thin monospaced numerals for the date range. [Subject] A wide squat amber cream jar, a tall tapered rose-gold tube and a round lidded pot arranged among stacked sage-green and gold gift boxes; behind them a small folded-paper fir with a gold star, strings of warm bulbs, one lit pillar candle and scattered baubles in gold and blue. [Lighting & mood] Soft directional studio glow, glassy reflections, luxurious and calm. [Details] Dewy metal highlights, glossy jar surface, faint sprinkling of fake snow, warm rim light on the boxes. Text: "RADIANT CHRISTMAS", "DEC 19 – 25".Professional holiday sale poster, vertical, bold flat vector graphics. [Colors] signal red #D62828 background, forest green #1B6B4A blocks, sunflower yellow #FFC93C price table, pure white type accents. [Layout] angled headline stacked across the top, a rounded white banner beneath, a green callout block with a gift sack at upper right, a large yellow price table of dashed rows across the lower half, QR block at the base. [Typography] extra-bold italic sans with tight leading, slightly skewed for speed; numerals very heavy and oversized. [Subject] flat sack of presents, brass bells on a sprig, cartoon hand holding them, small tree and star icons. [Lighting & mood] punchy retail loudness, no shadows, high contrast, urgent. [Details] sticker-style white outlines, torn-paper edges, subtle halftone texture. Text: "HOLIDAY GIFT SEASON", "SPEND 300, SAVE 50", "GROUP EXTRA".Professional Christmas fair poster, vertical, cut-paper collage with a giant snow globe hero. [Colors] Sky blue (#BBDDE4), crimson banner and bow (#B0252B), cream and cocoa gingerbread house, teal miniature firs, warm gold window glow, red gingham base. [Layout] Vertical banner headline at the top on a red plate, a Latin greeting beneath, one huge globe filling the centre two thirds with a wide ribbon bow cinched at its base, and a printed gingham strip anchoring the bottom; small decorative snowflakes sit on the blue margins. [Typography] Heavy slab-serif caps in white on the red plate, a rounded display serif for the greeting, no body copy. [Subject] Inside the glass sphere: a gingerbread cottage with a wreath on its gable, a snowman at the door, pine trees with gold stars, stacked gifts, a waving Santa and a leaping reindeer among the branches of a decorated tree. [Lighting & mood] Bright studio light with painted highlights, festive and toy-like. [Details] Glossy rim reflections on the glass, curved glare streaks, cut-out shadows, chalky paper texture. Text: "CHRISTMAS FAIR", "MERRY CHRISTMAS".Christmas greeting poster, vertical, cinematic 3D night scene rendered like a film still. [Colors] Ink navy #0A1428 and steel blue #1D3557 depth, warm gold #FFC46B fairy lights, brick red #A5352F bridge steel, cream snow #EAF0F6. [Layout] Central perspective down a snow-covered bridge that funnels the eye to a giant lit tree; a ferris wheel arcs behind the skyline; gold script sits in the upper band above a short caption; the date line closes the bottom over the ploughed path. [Typography] Ornate high-contrast script with hairline flourishes for the greeting, small spaced sans for the supporting line and date. [Subject] A colossal fir wrapped in warm lights and red baubles stands on an arched gateway, a reindeer-drawn sleigh with a red-coated Santa rides away on the snowy road, tall towers flank the scene, and a neon ferris wheel glows behind the crown of the tree. [Lighting & mood] Cold blue air, hot amber spill, glittering bokeh, romantic winter night. [Details] Falling snowflakes, frozen cable stays, soft volumetric haze. Text: "MERRY CHRISTMAS", "12.25".Photoreal Christmas Eve interior photograph, vertical, night scene. [Colors] deep amber #C97A34 and honey #E8A94F interior, near-black #1B1410 exterior, cool slate #3E4A56 distant pines. [Layout] a nine-pane sash window fills the frame, a garland of baubles and bells swagged across the top edge, sill with stacked books and dried foliage at the bottom, dark curtain on the left. [Typography] none, purely photographic with no lettering. [Subject] a small Christmas tree glowing behind the lower-left panes, a lit gold star topper, warm fairy lights strung through the branches, snow falling outside. [Lighting & mood] candle-warm interior glow against a blue winter night, bokeh snowflakes, intimate and quiet. [Details] soft film grain, glass reflections, dust motes drifting in the light, shallow focus falloff, cold blue highlights on the painted sill, faint condensation at the pane corners.Professional Christmas workshop invitation poster, vertical, minimal outlined-light illustration on deep red. [Colors] Rich poinsettia red (#B21D24), pure white outlines with a soft outer glow, emerald and gold ornament fills, small cyan sparkles. [Layout] Logo lockup top-left, a heavy white headline across the top, a bracketed date line, the outlined tree centred with ornaments scattered inside its silhouette, three lines of invitation copy beneath, two pill-shaped info bars stacked, and a code square with contact lines at the foot. [Typography] Bold geometric sans with a slight white glow for the headline; thin sans in wide tracking for the date; small caps on the info pills. [Subject] A Christmas tree drawn as a single thick glowing outline, its interior filled with die-cut decorations: gold stars, a striped bauble, a green wreath, green mittens, a small bell and red boots. [Lighting & mood] Night-time glow, crisp and inviting. [Details] Snowfall dots of varying size, tiny snowflake icons, generous dark red margin. Text: "TREE DECORATING", "DEC 25", "1F ATRIUM".Christmas greeting poster, vertical, geometric paper-collage design on coarse grain stock. [Colors] Vermilion #E23A2E field with a coral-to-pink gradient lower half, forest green #1E7A4C triangles, metallic gold #D8A64B lines, cream #F4EDE0 and butter yellow shapes. [Layout] A torn-paper triangular tree of three stacked green shards dominates the upper two thirds, cut by thin diagonal gold rays that run past the page edges; a small date block sits left, a short caption right; the lower third is a clean pink band holding the lettering. [Typography] Warm hand-drawn brush caps with rough edges for the big greeting, a fine condensed roman for the date and micro captions. [Subject] The tree is formed from three flat green triangles of decreasing size, crowned by a glowing gold star, dotted with a cream coin, a gold heart, a yellow cube and small eight-point sparkles, with a white triangular bauble floating near its base. [Lighting & mood] Retro print warmth, risograph-like grit, quiet nostalgia. [Details] Visible paper fibres, speckled noise, gold sticks glittering at the intersections. Text: "MERRY CHRISTMAS", "12/25".Professional holiday sale poster, vertical, illustrated theatre scene. [Colors] crimson velvet #8E1B24 curtains with #D93A3A accents, snowy blue-white #DCE9F2 distance, pine green #17603C, buttery cream #F6E6C8 panels. [Layout] heavy drapes framing a tall sash window onto snow-covered peaks, a decorated tree at right, a narrow ticket-style coupon column on the left, a three-card promo strip pinned along the bottom edge. [Typography] bold condensed sans headline with a beveled 3D edge, small caps for the coupon rows, oversized price figures. [Subject] a cheerful Santa peeking over the headline, glass ornaments and ribbon bows on the tree, wrapped parcels stacked at the base. [Lighting & mood] soft daylight through the window, cozy red interior, eager shopping energy. [Details] falling snow specks, candy-cane striped borders, faint window frame shadows. Text: "HOLIDAY GIFT SEASON", "$20 OFF $199", "DEC 23-25".Professional Christmas greeting card, vertical, layered paper-cut craft style photographed as a flat object. [Colors] Deep pine green panel (#1E4A38), candy-cane red and white stripe border, kraft brown backing (#8A5A3C), mint and cream paper layers, small coral berry accents. [Layout] A tall card sits slightly rotated on a red surface with two crossed ribbon banners over its top edge; inside, a rounded arch of stacked paper hills holds the message block in the upper half, a holly sprig and paper clouds float above, and Santa in his sleigh rides a snow slope at the lower right with a gift box and candy cane protruding past the trim. [Typography] Chunky rounded sans, cream, centred; a small handwritten-style signature line at the lower right. [Subject] Santa with a red hat and gold beard drives a reindeer-led sleigh across cut-paper snow, with a green-and-white dotted gift box in the foreground. [Lighting & mood] Soft top light, crisp paper shadows, playful and handmade. [Details] Die-cut edges, drop shadows between layers, ribbon banner tails. Text: "MERRY CHRISTMAS", "TO YOU".Christmas greeting poster, vertical, flat vector cartoon illustration with soft gradients. [Colors] Grass green #3FA45B and deep forest #17694A, blush pink #F6C9CE, butter yellow #F5C542, coral #EE6A4B and pure white. [Layout] Split composition: a giant fir occupies the top half and bleeds off the right edge, a pale pink oval disc sits in the middle carrying a miniature scene, and a green lower third holds the stacked headline, a thin rule, one-line blessing and a small contact strip. [Typography] Flowing hand-brushed script for the main greeting, a smaller matching script beneath, light sans for the fine print. [Subject] A wide fir strung with warm fairy lights, topped by an oversized gold star, hung with a red bow, a Santa hat, and glossy red, orange and blue baubles; on the pink disc a Santa rides a sleigh piled with gifts, pulled by a leaping reindeer. [Lighting & mood] Bright, friendly, playful daytime cheer. [Details] Tiny four-point sparkles, clean flat shading, generous white breathing space. Text: "MERRY CHRISTMAS", "DEC 25".Professional Christmas live-stream background, vertical, luxury still-life photography. [Colors] champagne #EAD7BC and warm sand #C9A87C fading into pale ivory #FFFDF8, brushed gold #C79A4B trim, a single muted red #B03A3A accent. [Layout] soft-focus fairy lights and a blurred bokeh canopy across the top, a curved satin ribbon banner centred above, a glass cosmetic bottle on a small pedestal at mid-left, layered cream Christmas trees and a tiny snowy house on the right, three circular badges in a row along the bottom. [Typography] slim spaced serif in gold on the ribbon headline, hairline caption beneath. [Subject] frosted miniature trees and reindeer silhouette cut-outs suspended from the ribbon, drifting snow particles. [Lighting & mood] hazy backlight, glowing warm bokeh, serene premium beauty mood. [Details] shallow depth of field, fine glitter dust, gentle vignette. Text: "HOLIDAY GIFT EDIT", "BUY ONE, GET SIX".Professional Christmas greeting poster, vertical, flat gouache illustration on textured paper. [Colors] Brick red felt ground (#B32B28), cream and oat village walls (#F3E2C4), deep pine green (#1D5138), amber window light (#F0B45A), soft gold script. [Layout] Date in the top-right corner, a large warm script headline across the upper third, the snow globe centred on a wide base, a snowman at bottom-left and a penguin at bottom-right on the snow line, then one short wish line and a code square. [Typography] Rounded brush script with a warm gold fill, chunky serif caps for the lower line, tiny sans for the date. [Subject] A glass globe containing a decorated fir, three gabled houses with lit windows and a bell tower, all standing on a wooden base with a small nameplate; a top-hat snowman with orange scarf and a small blue penguin flank the globe. [Lighting & mood] Storybook evening glow, gentle and cosy. [Details] Black pine silhouettes along the horizon, snow caps, visible paper texture and painted edges. Text: "MERRY CHRISTMAS", "I WISH YOU A WARM NIGHT".Christmas greeting poster, vertical, layered paper-cut night scene. [Colors] Deep emerald #0B5C46 to mint #7FE3B4 aurora ribbons across a coal-black #06120F sky, with butter-yellow #FFD66B tree tiers, cream #F7F3E4 highlights and warm brick #B85C3E cottage roofs. [Layout] Centred stack: thin glowing display lettering across the top third, a small subtitle and date line beneath, then a huge triangular fir filling the lower two thirds, with a row of tiny lit village houses along the bottom edge and a small contact block at the very bottom. [Typography] Hairline art-deco serif capitals with sweeping swash crossbars, wide letter spacing, plus a delicate script line under the tree. [Subject] A layered fir built from scalloped paper scales graduating from cream at the crown to teal at the skirt, topped by a bright eight-point star, scattered with candy-red, mint and lilac baubles, and dusted with gold sparkles. [Lighting & mood] Aurora glow, quiet hush, magical stillness. [Details] Soft grain, blurred bokeh orbs, pale snow haze in the foreground. Text: "MERRY CHRISTMAS", "DEC 25".

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About Christmas sale and event poster designs

Christmas artwork usually fails in one of two ways: it is beautiful but has nowhere to put your offer, or it is a red banner with a pine branch stuck on top. These designs keep the seasonal mood in the background and the message in a dedicated zone - a price plate, a coupon strip, a countdown block, a date-and-venue panel - so your copy never has to fight the artwork.

The collection covers the three jobs people actually have in December. Atmosphere: a poster for a shop window, a quiet typographic piece, a gift still life. Selling: the Christmas sale poster, the last-order-date banner, the gift-guide promo, where legibility at thumbnail size matters more than decoration. And gathering: party invitations, market stall flyers, church service notices and year-end concert posters, which need a strong date block and room for a venue line.

What size should a Christmas story post be?

1080 x 1920 px (9:16). Keep the headline and the price inside the middle 80% of the frame so platform UI does not cover them, and leave the top 250 px clear if you plan to add a sticker.

Where should the price go on a Christmas sale poster?

Bottom third, on a solid plate rather than directly over the artwork. Patterns, snow and bokeh destroy contrast, and a price nobody can read is a price nobody reads.

What size is a Christmas party poster?

A3 (297 x 420 mm) is the safe default for a printed notice board or venue door; 1080 x 1350 px (4:5) is the equivalent for a feed post. Keep the date, time and venue in one block - people screenshot the image and only re-read that corner.

Can I use these for a Boxing Day or New Year sale?

Yes. The layouts without gift or Santa motifs are deliberately generic winter sale designs, so the same poster works for Boxing Day, end-of-year clearance and New Year promotions - swap the headline line and the date.