The Magnite–PubMatic spread, in 2026.
The two dominant SSPs price differently across different inventory. The spread tells a story about where each is winning — and where each is paying for share.
The SSP landscape in 2026 reads as a duopoly with footnotes. Magnite and PubMatic together account for the majority of programmatic supply-side share across CTV, video, and premium display. Index Exchange holds the third seat. Equativ has consolidated the long tail into one stack. The rest is path noise.
But the duopoly isn’t symmetrical. Magnite and PubMatic price differently across inventory types — and the spread is reportable.
Where Magnite leads
CTV. The 2024 acquisition of SpringServe and the existing publisher relationships keep Magnite’s CTV path-economics tight. Auction-fee leakage on Magnite CTV paths is typically lower than on PubMatic-routed equivalents. The CTV story is Magnite’s to lose.
Where PubMatic leads
Mobile in-app and emerging-market video. PubMatic’s OpenWrap header-bidding stack has pulled mobile share through 2025–2026. Their working margins reflect it. For brands buying mobile in-app at scale, the PubMatic path is meaningfully cheaper at the line item.
Display, split
Premium display is the contested layer. Both SSPs have parity supply, parity tooling, parity fees. The differentiator on display is which DSP you’re buying from and which header-bidding stack the publisher prefers — neither SSP wins it on its own.
The read
The right SSP isn’t a portfolio decision. It’s a per-inventory decision.
“CTV through Magnite. Mobile in-app through PubMatic. Display split.”
For 2026 strategy work, the implication: don’t write SSP allocation as a percentage of total spend. Write it as a routing decision per inventory class. Track the fee spread quarterly. Adjust when the spread inverts on any class — which it will, because the SSPs are competing for the upper hand on every category they share.
A working note. If you want to compare your own SSP path economics — direct line at hello@odellnco.com.