Supply-Side Platform Explained: How It Powers Programmatic Advertising for Publishers

Ad tech loves its three-letter acronyms, and one of the most commonly heard ones is SSP, short for supply side platform. So, what are supply-side platforms? Who uses them? And how do they work? Here’s everything you need to know.

As a publisher, your primary goal is to deliver relevant and engaging content to your audience, while also building sustainable revenue streams. That’s where SSPs come into play. These platforms act as intermediaries, connecting you with a vast network of advertisers eager to display their ads on your website. 

From understanding SSP functionalities to leveraging their advantages, here’s what every publisher should know to optimize ad revenue.

Now, without further ado, let’s dive right into the heart of the matter.

What is a Supply-Side Platform?

A supply-side platform (SSP), also known as a sell-side platform, is a technology platform that enables web publishers to manage their ad inventory, fill it with ads, and receive ad revenue. That’s pretty much it. However, we cannot explain what is a supply side platform without touching base on what a demand side platform is. 

So, let’s try to understand what is a demand side platform.

What’s a Demand-Side Platform?

Demand-side platforms are utilized by advertisers to buy ad space, made available by the publishers, for the purpose of running ad campaigns.

The main function of a DSP is to help advertisers buy ad impressions from ad exchanges as cheaply and efficiently as possible, while the main function of an SSP is to help publishers maximize ad revenue. Both platforms run on similar technologies but are used at different ends of the transaction.

We have covered that in detail in our blog – Demand-side Platforms (DSP). Want to understand the programmatic web to the brim? Don’t forget to go through our blog.

Supply-side Platform (SSP) vs Demand-side Platform (DSP)

	SSP (Supply Side Platform)	DSP (Demand Side Platform)
Purpose	Maximize revenue and ad performance for publishers	Help advertisers reach audiences and make campaigns efficient
Control	Publishers have inventory control	Advertisers have bidding control
Ad Placement	Optimize ad placement on websites	Target specific audience segments
Data Usage	Utilize publisher data for targeting	Utilize user and third-party data
Relationship	Connect with DSPs to sell inventory	Connect with SSPs to buy inventory

Now that we have fully covered “what is a supply side platform”, let’s understand how it works.

How Does a Supply Side Platform Work?

Just like with every AdStack, it starts with a code: The SSP provides publishers with a code that they embed within their website’s source code. This integration opens up the inventory to SSPs and gives it access to the ad units.

1. Whenever there’s a visitor to the website, the SSP issues ad requests to multiple ad networks, ad exchanges, and DSPs simultaneously. 

2. Advertisers bid on the impression. Based on the ad unit’s parameters and advertisers’ requirements, the SSP selects the best ad at the highest bid.

3. The ad server then compares the bid with other programmatic deals that the publisher might have, and selects the highest bid.

The underlying principle of SSP is the economics of supply and demand. By increasing the demand pool for a publisher’s ad inventory, SSPs increase the value of the publisher’s ad inventory. For this reason, SSPs are also sometimes called “yield-optimization platforms”.

How does an SSP Assist in Ad Space Selling? (Functions of an SSP)

Programmatic advertising has automated the buying and selling of ad space, introducing new efficiencies and complexities for publishers. Supply-side platforms (SSPs) step in as key allies for publishers by helping them manage their ad inventory, connect with advertisers, and maximize revenue in this fast-moving environment. 

Here’s how SSPs bring value to publishers:

1. Frequency Capping

SSPs and DSPs work together to limit the number of times a visitor sees an ad. It records the frequency at which an ad is shown to a user and caps it to negate ad fatigue.

2. Supply Path Optimization

SSPs assist publishers in identifying the best demand sources for their needs, taking into account criteria such as latency, unique demand, bid pricing, and ad space availability.

3. Real-time Bidding (RTB) Enablement

SSPs enable inventory to be sold in real-time auctions by making it accessible to a large number of demand-side platforms, networks, and ad exchanges. 

4. Automation

SSPs decrease publishers’ manual efforts by automating most of the processes like bidding, ad placements, and reporting. This efficiency allows publishers to focus on strategy while maximizing ad revenue. 

5. Inventory Management

Publishers use SSPs to control the way their inventory is sold by defining parameters like floor prices, acceptable ad formats, and preferred advertisers.

6. Performance Tracking and Reporting

The SSP gives publishers insights to maximize inventory sales by tracking the effectiveness of ad placements, including impressions, clicks, and revenue generated.

7. Revenue Optimization

The SSP continuously optimizes inventory pricing and buyer matching using algorithms and historical data to maximize revenue for publishers while maintaining ad quality and inventory value.

What are the Main Components of a Supply-side Platform?

Here are the main components of a Supply-Side Platform (SSP):

1. Ad Exchange Integration

An SSP connects publishers to a network of ad exchanges. These exchanges act as marketplaces where advertisers (through DSPs) and publishers (through SSPs) can connect to buy and sell ad inventory.

2. Backend and Infrastructure

To provide services to publishers and sell ad space, an SSP’s numerous backend components must be housed on an infrastructure (e.g., Amazon Web Services). From there, they can execute all of the technical operations that power the SSP’s functions.

3. Trackers

Trackers gather information about the publisher’s website and readership. It subsequently forwards this information to other components, such as the user profile database and the reporting database.

4. Reporting Database

The tracker sends campaign and audience data to the reporting database, allowing publishers to create reports and examine campaign analytics.

5. Yield Optimization

Many SSPs offer yield optimization tools that use data and analytics to maximize revenue from ad inventory.

What Are the Main Features of a Supply-side Platform?

SSPS has multiple features that make the publisher experience easier and less cumbersome. Here are the main features of a Supply-Side Platform (SSP):

1. Demand Forecasting and Floor Price Optimization

By analyzing data, the SSP can predict future demand for specific ad placements, allowing publishers to adjust pricing strategies to capitalize on peak periods.

2. Ad Format Optimization

The SSP can recommend the most suitable ad formats (display ads, video ads) for different placements, considering factors like user behavior and potential revenue per format.

3. Programmatic Deals

It lets publishers execute private marketplaces (PMPs) and programmatic guaranteed transactions, apart from ad space selling via open RTB.

4. Ad Quality Filters

Through ad quality filters, publishers can block specific advertisers and certain ad formats or filter out certain ads that do not align with their audience.

5. Real-time Dashboards

SSPs offer publishers real-time, detailed analytics on impressions, clicks, revenue, and audience demographics that help them assess performance and optimize campaigns.

What are the Benefits of Using a Supply-side Platform?

Let’s now have a look at the wide array of benefits a supply side platform has to offer.

1. Maximized Revenue

With real-time bidding enabled along with other programmatic deals, an SSP creates a conducive environment for the publisher. Combining historical data and advanced analytics, SSPs ensure that publishers get maximum eCPMs for their ad space.

2. Transparency and Control

With SSPs in place, publishers know how their ad space is being sold. They know who all are taking part in the auction and bidding on it, what ad will be shown, and what would be the ad format. This gives publishers the control to decide the kind of ads they want to display for their audience.

3. Brand Safety

Because SSPs can be configured to supply inventory to specified buyers or through specific channels exclusively, they can provide greater brand protection by preventing undesired ads from appearing on your website.

4. Automated Ad Selling

The most important advantage of an SSP is automation. SSPs remove the manual work from the ad-selling process, bringing in more efficiency and accountability.

Supply Side Platform vs. Ad Exchange

Aspect	Supply Side Platform (SSP)	Ad Exchange
Primary Role	Manages ad inventory and revenue for publishers	Neutral marketplace connecting SSPs with DSPs
Main Function	Optimizes yield, sets floor prices, enables targeting and reporting	Facilitates real-time bidding (RTB) auctions
RTB Involvement	Sends ad requests to exchanges	Executes auctions and selects winning bids
Position in Stack	Closer to publisher in the tech stack	Sits between SSPs and DSPs
Revenue Focus	Maximizes publisher revenue	Balances supply and demand for optimal bidding

How Targeting Works in a Supply Side Platform?

An SSP utilizes various data sources to perfect its targeting. And to further its cause, it uses various targeting mechanisms to achieve its means. Some of them include:

1. Demographic Targeting

Publishers can reach users who are more likely to convert by segmenting audiences based on variables like age, gender, and income.

2. Behavioral Targeting

SSPs utilize user data, such as browsing history or prior interactions via cookies, to deliver relevant ads. For example, a user who has searched for iPhones will be shown iPhone-related ads.

3. Contextual Targeting

As the name suggests, ads are displayed that are in context to the current webpage’s content. For example, a user reading about dog breeds may be shown pedigree ads.

4. Device Targeting

Ads are personalized to the user’s device (mobile, desktop, or tablet) to deliver a better viewing experience and interaction.

5. Geographical Targeting

Ads are served based on the user’s location, allowing brands to run targeted regional and local campaigns with greater precision.

6. Time-based Targeting

Campaigns are timed to run when the target audience is most active, ensuring ads are shown during peak engagement periods.

How Does a Supply Side Platform Make Money?

Many SSPs like Google AdSense don’t charge any fees from publishers for joining. So, how do they survive? Or cover their operational costs? Here’s how:

1. Ad Serving Fees

Some SSPs additionally serve as ad servers, hosting and delivering advertising to publishers’ websites for a fee.

2. Transaction Fees

SSPs take a cut from the publisher’s revenue for every ad space sale.

3. Platform Usage Fees

Certain SSPs charge a one-time fee to use their platform, particularly for premium or advanced features.

4. Managed Services

Apart from automated sales, some SSPs also offer managed services, which include participating actively in optimizing the publisher’s revenue for a fee.

5. Data Fees

SSPs can generate revenue by monetizing user and impression data, offering these insights to advertisers or third parties for a fee.

What To Consider When Choosing a Supply Side Platform?

If you are looking for the best supply-side platform, here’s what you should look for:

1. Ad Formats and Inventory Management

Select an SSP that offers the display, video, native, CTV, and other ad formats that suit your requirements. Additionally, it should provide inventory control features like price floors, ad blocking, and private deals.

2. Data and Reporting Capabilities

Choose an SSP that offers real-time reporting that includes insights on audience, revenue, and ad unit performance, among others. The consolidated data will help you polish your strategies and maximize your yield.

3. Integration and Support

Opt for an SSP that offers quick and easy integration with your website. For example, you can set up Google AdSense with a single line of code. For websites that CMS manages, it offers plugins or extensions for code integration. Moreover, make sure that customer support is reliable in case you face any glitches and need prompt assistance.

4. Brand Safety and Ad Quality

To preserve the user experience, the SSP should also provide fraud protection and brand safety tools to block ads that don’t align with your publishing business.

5. Monetization Opportunities

Apart from the basic features, the SSP should also offer advanced monetization features, such as dynamic ad insertion, header bidding, or other video monetization options.

7 Best Supply Side Platforms In 2025

Supply-Side Platforms (SSPs) are an essential tool for publishers in the programmatic advertising world.  Here are some of the leading SSPs to consider in 2025:

SSP	Features
Teads	– Offers premium, omnichannel ad placements across top publishers   – Uses AI for personalized, contextual ad delivery   – Focuses on high-impact, non-intrusive formats to balance UX and revenue
C Wire	– Built for cookieless, privacy-first advertising   – AI-powered contextual targeting across all browsers   – Outcome-based bidding with transparent, real-time reporting
Verve	– Direct access to top brand advertisers and agencies   – Supports high-impact ads across mobile, CTV, and web   – Enables private marketplaces and data-enriched monetization   – Has partnered with Remerge for on-device bidding through Google’s Privacy Sandbox on Android
PubMatic	– Supports omnichannel monetization across screens and formats   – Offers customizable programmatic deal models   – Provides strong analytics and ad quality tools
Magnite	– Specializes in CTV/OTT via SpringServe platform   – Combines ad serving, mediation, and yield management   – Enables advanced deals and marketplace packaging
Google Ads Manager	– All-in-one platform for ad serving and monetization   – Supports Open Bidding and dynamic allocation   – Trusted, scalable solution with global reach
Xandr Monetize	– Integrates with Microsoft Advertising for broader reach   – Optimizes both direct and third-party campaigns   – Allows granular control over ad quality and delivery

Key Takeaways on Supply Side Platform

1. What is a supply side platform: It is a programmatic advertising platform that enables publishers to sell and manage their ad inventory to earn ad revenue.
2. Functions of an SSP: Frequency capping, supply path optimization, automation, inventory management, performance tracking, and revenue optimization.
3. Components of an SSP: Ad exchange integration, backend and infrastructure, tractors, reporting database, and yield optimization.
4. Benefits of an SSP: Maximized revenue, detailed performance insights, transparency and control, brand safety, and automated ad selling.
5. Factors to consider while choosing an SSP: Ad formats and inventory management, data and reporting capabilities, integration and support, brand safety and ad quality, and monetization opportunities.

FAQs: Supply Side Platform