What Are the Benefits of Using RLSAs?

Why Remarketing Lists for Search Ads Work

Most people who visit a website don't convert on their first visit, particularly for considered purchases with a longer research phase. RLSAs, remarketing lists for search ads, give advertisers a way to recognise those previous visitors when they come back to Google and search again, and to respond differently to them than to someone searching for the very first time.

This guide explains what RLSAs are, how they work, how they differ from standard search advertising, and the genuine benefits they bring, particularly for B2B businesses with longer buying cycles. It builds on our wider Google Ads strategies for UK businesses and complements our guide to how Google Ads works, drawing on how we apply remarketing strategy through our Google Ads agency service.

Key takeaways

RLSAs let advertisers adjust bids and ad messaging for people who've previously visited their site when they search again.
RLSAs work as an audience layer added to existing search campaigns, not a separate campaign type.
Benefits include reconnecting with warm audiences and tailoring messaging to where someone is in their buying journey.
RLSAs don't automatically reduce cost per click or guarantee a higher conversion rate.
They're particularly useful for B2B businesses with longer research and decision cycles.
Audience lists must comply with privacy requirements and have sufficient size before they can be used.

What are RLSAs?

RLSAs, remarketing lists for search ads, are an audience targeting feature within Google Ads that lets advertisers customise their search campaigns for people who've previously visited their website. Rather than creating an entirely separate campaign, RLSAs are typically applied as an audience layer on top of existing Search campaigns, allowing bid adjustments and, in some setups, tailored ad copy for visitors who return to Google and search again after leaving a site without converting.

How do remarketing lists for search ads work?

When someone visits a website with the Google Ads remarketing tag installed, they can be added to an audience list based on the pages they visited or actions they took. If that same person later performs a relevant search on Google, an advertiser using RLSAs can bid differently for that auction, and in some cases show different ad copy, because the search engine recognises them as a known visitor rather than someone searching cold. Lists need to reach a minimum size, generally at least 1,000 active users for Search, before Google will allow them to be used for targeting.

RLSA vs standard search advertising

How RLSAs differ from standard Google Ads search targeting
Factor	Standard search advertising	RLSA
Audience knowledge	No prior signal about the searcher	Recognises previous site visitors
Bidding	Same bid strategy regardless of history	Can adjust bids for known warm audiences
Messaging	Generic to all searchers	Can be tailored to visitors further along the journey
Best suited to	Capturing new, cold demand	Re-engaging people already familiar with the business

Key benefits of RLSAs

Reconnecting with previous visitors who didn't convert on their first visit, keeping the business visible as they continue researching.
Audience-informed bidding, allowing advertisers to bid differently for people already familiar with the business than for entirely new searchers.
Tailoring search strategy to warmer audiences, since a returning visitor typically needs different messaging than someone searching cold.
Segmentation, letting advertisers treat visitors who viewed pricing pages differently from those who only viewed general content.
Potentially improving efficiency by directing more nuanced targeting toward audiences already showing interest, though this isn't guaranteed for every account.
Supporting longer buying journeys, where a single visit rarely leads directly to a conversion.

RLSA examples for B2B businesses

A B2B software company might use RLSAs to bid more competitively when a previous website visitor searches a relevant commercial term again a week later, reflecting the fact that this person is a known prospect rather than a cold searcher. Alternatively, a business might tailor ad copy differently for visitors who previously viewed a pricing or demo page compared with those who only read a blog post, recognising that they're likely at different stages of the buying journey.

RLSAs and longer B2B buying cycles

B2B purchases often involve multiple stakeholders and a research period spanning weeks or months, during which a prospect may search several times before ever making contact. RLSAs give advertisers a way to remain visible and relevant across that extended journey, rather than treating every search as an isolated, one-off event disconnected from the prospect's history with the business.

Targeting vs observation considerations

RLSA audiences can generally be applied in "targeting" mode, restricting ads to only that audience, or "observation" mode, keeping the campaign open to everyone while allowing bid adjustments and reporting for the audience. Observation is often the safer starting point, since it lets advertisers see how a remarketing audience performs without restricting reach, while targeting mode suits more deliberate campaigns aimed specifically at re-engaging known visitors.

Privacy, consent and audience requirements

Building remarketing lists depends on tracking technology and requires appropriate cookie consent and privacy disclosures in line with UK data protection requirements. Audience lists must also meet Google's minimum size thresholds before they can be used, and advertisers should keep list definitions and retention periods aligned with their privacy policy, reviewing them periodically as platform requirements and consent frameworks continue to evolve.

Common RLSA mistakes

Applying the same bid adjustment and messaging to every remarketing audience regardless of how engaged they were.
Assuming RLSAs will automatically lower cost per click or lift conversion rates without ongoing review.
Letting lists sit unreviewed, without refining segments as more visitor data becomes available.
Overlooking consent and privacy requirements when setting up remarketing tags.

When RLSAs may not be appropriate

RLSAs depend on having enough website traffic to build audience lists that meet Google's minimum size requirements, so very low-traffic websites may need to focus on growing visitor numbers before remarketing becomes viable. They're also less useful for genuinely one-off, impulse-driven purchases where a returning-visitor signal adds little to the targeting decision.

Frequently asked questions

What does RLSA stand for?+

RLSA stands for remarketing lists for search ads, a Google Ads audience feature that lets advertisers adjust bids and messaging for people who've previously visited their website.

Do RLSAs cost more than standard search campaigns?+

Not inherently — RLSAs are an audience layer applied to existing search campaigns, and any cost difference comes from the bid adjustments an advertiser chooses to apply, not a separate pricing model.

How big does my remarketing list need to be to use RLSAs?+

Google generally requires an audience list to reach at least 1,000 active users for Search campaigns before it can be used for RLSA targeting.

Do RLSAs guarantee a better conversion rate?+

No. RLSAs can help tailor bidding and messaging to warmer audiences, but they don't automatically guarantee lower cost per click or higher conversion rates, and results still depend on how well they're set up and reviewed.

Are RLSAs suitable for B2B businesses?+

Yes, RLSAs are particularly useful for B2B businesses because longer buying cycles and multiple stakeholders mean prospects often search more than once before making contact.

Should I use targeting or observation mode for RLSAs?+

Observation mode is often a sensible starting point, since it allows reporting and bid adjustments for a remarketing audience without restricting the campaign's overall reach.

Do RLSAs require cookie consent?+

Yes, building and using remarketing lists relies on tracking technology that requires appropriate cookie consent and privacy disclosures in line with UK data protection requirements.

Conclusion

RLSAs give advertisers a genuinely useful way to recognise previous website visitors and adjust bidding and messaging accordingly, particularly valuable for B2B businesses navigating longer buying cycles. They're not a guaranteed shortcut to lower costs or higher conversion rates, but used thoughtfully alongside strong audience segmentation, they add a layer of relevance that standard search targeting alone can't provide.

If you'd like help setting up or refining remarketing strategy within your Google Ads account, our Google Ads agency team can talk through the options.

Glossary of Terms

RLSA: Remarketing lists for search ads, a Google Ads audience feature allowing advertisers to adjust bids and messaging for previous website visitors who search again.
Remarketing: The practice of showing ads to people who have previously interacted with a business, typically after visiting its website.
Audience list: A group of users defined by shared behaviour, such as visiting a specific page, used for targeting or bid adjustments.
Targeting mode: An RLSA setting that restricts a campaign to show ads only to a defined audience.
Observation mode: An RLSA setting that keeps a campaign open to all eligible searchers while still allowing bid adjustments and reporting for a defined audience.
Bid adjustment: A percentage increase or decrease applied to a base bid for a specific audience, device, location or time.
Remarketing tag: A snippet of code placed on a website that allows visitor behaviour to be recorded and used to build audience lists.
Buying cycle: The period between a prospect's first engagement with a business and their eventual purchase decision.
Segmentation: Dividing an audience into distinct groups based on behaviour or characteristics, to allow more tailored targeting.
Consent management: The process of obtaining and recording user permission for tracking technologies such as cookies, in line with privacy regulations.