The Challenge
Q4 compresses decision-making timelines, inflates CPMs, and punishes brands whose campaign structure is misaligned with how platform algorithms allocate budget and signal. For ONE/SIZE, entering peak without reliable measurement of which channels and setups were genuinely performing was not viable.
On Meta, the account had accumulated the hallmarks of a fragmented setup: too many small, segmented campaigns; high-spend creatives inside low-ROAS structures; no consistent Hero SKU messaging.
On TikTok, the challenge was conviction. GMV Max had recently launched and most brands were treating it cautiously. The on-platform ROAS looked modest, and without measurement that could surface cross-channel halo effects, the case for scaling it aggressively was hard to make internally.
The Solution
Fospha’s role across both platforms was consistent: measurement clear enough to act on quickly, and the strategic context to turn platform change into in-season advantage.
Meta: Andromeda-Aligned Consolidation
ONE/SIZE restructured their Meta account ahead of Q4 to match what Andromeda rewards - consolidating into fewer, larger campaigns with diversified creative, and re-anchoring spend and messaging to top-performing Hero SKUs. Fospha’s incrementality view then fed back which creatives were genuinely scaling versus burning budget, enabling in-flight reallocation rather than end-of-quarter review.
TikTok: Early GMV Max Scaling
In Q4 2024, GMV Max was a negligible test line. By Q4 2025, it was ONE/SIZE’s single largest channel at 42% of total media budget. That shift was made defensible by Fospha’s full-funnel attribution, which surfaced GMV Max’s halo into Direct, Organic Social, and Paid Search - proving the true return extended well beyond what on-platform ROAS alone would suggest. Three pillars drove the scale-up:
- Creative diversity: wide asset variety to prevent algorithm fatigue at peak
- Affiliate programme integration: affiliate content used as GMV Max fuel, still under-adopted in the wider market
- Hero SKU dedicated budget: ring-fenced spend to give the algorithm a clean optimization target
The Results:
ONE/SIZE's Q4 2025 results turned Fospha's measurement into exceptional performance - at both channel-level and overall. The team achieved 35% blended revenue growth year-over-year on 53% higher spend - a deliberate investment in new customer acquisition. Underlying media efficiency improved meaningfully: CPMs fell 23%, CTR grew 53%, and AOV rose 6%. Conversions grew 27% YoY.
On Meta, ROAS more than doubled (+164% YoY) and CAC fell 65%, with revenue growing 329% against a 62% increase in spend. New customer ROAS improved 145%.
On TikTok, combined channel ROAS rose 421% YoY as GMV Max scaled from a test line to the brand’s primary growth channel. Revenue grew 525% on 22% more spend.
“We’ve always believed in moving early on new platform mechanics - but moving early only works if you trust the data behind the decision. Fospha gave us the measurement confidence to scale GMV Max when most brands were still waiting, and to restructure our Meta account in a way that felt counterintuitive but turned out to be exactly right. Q4 proved both bets.” - Niket Shah, Co-founder, Acceler8 Labs
The Bottom Line
ONE/SIZE’s Q4 2025 results show what happens when platform fluency meets measurement brands can act on: two major platform shifts delivered step-change results within a single quarter. Fospha’s role was to provide the real-time clarity that made bold, in-season decisions defensible - and fast enough to matter.
Footnotes
- Impact type: Blended impact (full-funnel, Fospha-measured) and channel-specific (Meta and TikTok).
- Time range & period comparison: Q4 2025 (October–December 2025) vs Q4 2024 (October–December 2024), YoY.
- Market: United States (US).
