We Analyzed 11,500 Google Maps Listings Across 25 Cities After the March 2026 Update — Here's What Actually Changed

While optimizing a client's insurance agency Google Business Profile through the March 2026 core update, we noticed something: businesses with keyword-stuffed names appeared to be climbing into positions they shouldn't occupy, while established businesses with clean profiles held steady — but only if their review volume was high enough. We'd seen this pattern before. In 2025, we analyzed 7,178 HVAC listings across 100 cities and found systematic spam displacement. We decided to test whether the March 2026 update made this better, worse, or different — across 8 verticals, 25 cities, and 11,500 Google Maps listings.

Before publishing, we tested 121 queries across four AI platforms — Google Gemini, ChatGPT, Perplexity, and Claude — to determine what original data existed on this topic. ChatGPT explicitly confirmed 9 of 14 queries had no original data available. Claude reported that "truly independent original data specifically isolating the update's effect on Google Maps rankings is not yet available." This study is the first primary dataset to fill that gap.

Key Findings From 11,500 Listings

• 27.5% of local pack businesses changed between January and March 2026 across 110 matched comparisons — the first before/after measurement of the March 2026 update's local impact.
• 27.7% of top-3 dental listings show clear keyword manipulation — the highest rate of any vertical in the IMPIOUS 2026 study, based on severity 2+ detection (business name contains service keyword plus city name or multiple keyword phrases).
• Top-3 businesses average 445 Google reviews versus 391 for positions 4-10, but the gradient is noisy — position 6 averages more reviews (462) than position 3 (395).
• Review velocity is inverted: top-3 businesses add 7.06 reviews/month while positions 4-10 add 8.72/month. Established businesses slow down; climbing businesses show burst activity.
• GBP completeness shows a 1-point gap between top-3 (58.2/100) and positions 4-10 (57.1/100) — confirming completeness is a binary threshold, not a competitive gradient.
• 20.5% of Google Maps results change when users add "near me" to a search — proving Google treats "near me" as a distinct intent signal, not just a proximity modifier.
• No AI platform could cite original local data for the March 2026 update. Across 121 prompts tested against Google, Brave, and Perplexity search indexes, the most-cited domains were brightlocal.com (15 citations), searchengineland.com (15), and sterlingsky.ca (11) — none with original post-update local ranking data.
• In Grand Rapids, one plumber dominates 25 of 49 geogrid points while dental shows 34% keyword manipulation across the grid — a city-level view of how local search competition actually works.

How much did the March 2026 update actually change local pack results?

Between January and March 2026, 27.5% of local pack businesses changed across 110 matched keyword-city comparisons in the IMPIOUS 2026 study. 130 new businesses entered the top 3 while 412 dropped out. Only 32.7% of local packs were completely unchanged.

This is the first before/after measurement of the March 2026 core update's impact on local search, made possible by comparing DataForSEO's historical SERP snapshots (January 2026) against current April 2026 Google Maps data for the same keyword-city combinations.

The churn was not uniform across industries:

Plumbing and HVAC experienced the highest churn — approximately 1 in 3 local pack positions changed hands. Insurance showed the most stability, though the sample was smaller. The March 2026 update triggered measurable reshuffling in Google Maps results, particularly for service-based verticals where competition is dense.

Methodology note: Historical data availability varied by keyword and city. Of 500 attempted comparisons, 110 returned usable matched pairs with both pre-update and post-update snapshots. Results are directional, not definitive, given the sample limitations.

What percentage of Google Maps top results show keyword manipulation?

Across 11,500 Google Maps listings in the IMPIOUS 2026 study, 6.3% show clear keyword manipulation at severity level 2 or higher — meaning the business name contains a service keyword combined with a city name, or multiple keyword phrases designed to match search queries rather than reflect the actual registered business name.

Among top-3 positions specifically, the rate varies dramatically by industry:

Dental stands out as the most affected vertical, with more than 1 in 4 top-3 positions held by listings showing keyword manipulation patterns. This is consistent with Sterling Sky's earlier keyword stuffing research across 5,306 listings, but our dataset is 2.2x larger and covers 8 verticals post-March 2026 — a combination no prior study offers.

Severity scoring methodology: We detected keyword manipulation using a 4-tier system. Severity 0 (clean) = business name contains no search keywords. Severity 1 (mild) = name contains one service-related keyword, which may reflect natural naming in some industries. Severity 2 (moderate) = name contains a keyword plus city name. Severity 3 (severe) = name contains multiple keywords or keyword + city + modifier. Only severity 2+ is reported as "keyword manipulation" — this conservative threshold reduces false positives from industries where service terms naturally appear in business names.

City-level variation: Des Moines showed the highest top-3 manipulation rate at 21.7% (across all severity levels), while Dayton was cleanest at 10.1%. The full city-by-city breakdown is available in the downloadable dataset.

How many Google reviews do businesses need to rank in the top 3?

Top-3 businesses on Google Maps average 445 reviews compared to 391 for positions 4-10 in the IMPIOUS 2026 study — a 14% gap. However, the relationship between review count and ranking position is not the smooth gradient the industry assumes.

Position 6 averages 462 reviews — MORE than position 3 (395). Position 4 (426) outpaces position 5 (372). Review count alone does not determine ranking position. Google's local algorithm weighs proximity, relevance, and multiple prominence signals; review count is one factor among many, and its effect is strongest at the very top (positions 1-2 averaging 470 vs. the rest averaging 403).

ChatGPT estimated that top-3 businesses need approximately 200+ reviews. Our data shows the actual number is more than double that — 445 on average — though this varies dramatically by vertical:

Note: Restaurants show an inverted pattern — positions 4-10 average MORE reviews (896) than top-3 (661). This likely reflects Google weighting cuisine type, proximity, and hours more heavily than review count for restaurant queries. A taco shop with 200 reviews in your neighborhood may outrank a steakhouse with 1,000 reviews across town.

Data coverage note: Review count and rating figures are based on the full 11,500 listings. Review velocity and owner response rate (in subsequent sections) are based on a 1,514-listing subset where detailed review data was available (13.2% coverage) and should be treated as directional.

Does review velocity predict Google Maps ranking?

Review velocity — the rate of new reviews per month — is inversely correlated with ranking position in the IMPIOUS 2026 study. Top-3 businesses add 7.06 reviews per month while positions 4-10 add 8.72 reviews per month. This counterintuitive finding challenges the widely-held industry assumption that higher review velocity drives higher rankings.

The explanation is structural: businesses that already dominate positions 1-2 have accumulated large review bases (470+ average) and their monthly growth rate naturally declines as a percentage of total. Meanwhile, businesses in positions 4-10 are often in active growth phases — investing in review generation, responding to competition, and showing the burst activity that comes with trying to climb. Velocity reflects ambition, not authority.

A business owner who sees a competitor adding 10 reviews per month while they add 5 shouldn't panic — the competitor may be climbing from position 8, not threatening from position 1. Total accumulated reviews appear to matter more than recent velocity in determining sustained ranking position.

Does GBP completeness affect Google Maps ranking?

GBP completeness shows a 1-point gap between top-3 and positions 4-10 in the IMPIOUS 2026 study. Top-3 businesses scored 58.2 out of 100 on our completeness index versus 57.1 for positions 4-10. This near-zero difference confirms completeness functions as a binary threshold — you need a minimum level to compete, but additional optimization beyond that baseline yields diminishing returns for ranking position.

87.7% of top-3 businesses have a website linked in their GBP. 31.1% have 25 or more photos. These are table-stakes metrics, not competitive advantages. The businesses without a website or without photos are at a genuine disadvantage — but once those basics are met, the ranking battle is fought on other signals.

Methodology note: GBP completeness scores were derived from Google Maps listing data (website presence, phone, rating, review count, photo count, category specificity) rather than direct GBP profile pulls. The DataForSEO Business Data API returned limited profile data (21 of 1,003 lookups succeeded), so completeness metrics exclude hours, description, and attributes. The actual completeness gap may be larger than our data shows. We report what the available data supports.

What happens when users search "near me" versus standard queries?

When users add "near me" to a local search, 20.5% of the top-5 Google Maps results change compared to the same query without "near me," based on 125 comparisons across 5 keywords and 25 cities in the IMPIOUS 2026 study. Google treats "near me" as a distinct intent signal that adjusts result composition, not merely a proximity modifier that reorders the same businesses.

Plumber queries show the most divergence — more than 1 in 4 results change. This likely reflects the higher density of plumbing businesses and stronger proximity weighting for emergency-intent services. Boise (68% overlap) and Greensboro (68%) showed the most city-level divergence, while Dayton (92%) and Chattanooga/Tallahassee (88%) were most stable.

If you only track your ranking for standard keywords, you're blind to 20.5% of how your customers actually search. Set up separate rank tracking for both "plumber" and "plumber near me" in your market. The businesses showing up in one but not the other are the competitive gap you didn't know existed.

Grand Rapids Geogrid: How Local Search Competition Actually Works

In a 7×7 GPS coordinate grid across Grand Rapids, MI — 49 measurement points spanning the metro area — the IMPIOUS 2026 study mapped which businesses dominate each position for 5 key verticals.

Plumbing: Mountaineer Plumbing appeared in the top 3 at 25 of 49 grid points and held the #1 position at 9 points. 29 unique businesses appeared across the grid. Keyword manipulation was minimal at 0.7%.

HVAC: The most fragmented market — 48 unique businesses across 49 grid points. Simple Heating and Air led with 14 top-3 appearances. No single business dominated the city.

Dental: 66 unique businesses competed, but 34% of top-3 grid positions showed keyword manipulation. Great Lakes Dental Care led with 13 top-3 appearances.

Personal Injury Lawyer: The most concentrated market — Michigan Auto Law appeared in the top 3 at 32 of 49 points. Only 18 unique firms appeared. 19.7% showed keyword manipulation.

Insurance: 66 unique agencies competed. 87.8% of grid positions contained the word "insurance" in the business name — though much of this reflects natural naming conventions in the insurance industry rather than intentional manipulation.

What did AI platforms say when we asked about this data?

Before publishing this study, we queried 4 AI platforms with 121 prompts to map the current citation landscape for local search data after the March 2026 update. This was not a test of AI accuracy — it was reconnaissance to identify exactly which data gaps our study fills.

ChatGPT (14 prompts, Bing index): Explicitly confirmed 9 of 14 queries had no original data available. When asked "Has anyone published original data on how Google's March 2026 core update affected local business rankings on Google Maps?" ChatGPT responded: "No serious, large-scale original data study has been published on March 2026 update impact on Maps."

Claude (31 prompts, Brave Search): Confirmed 4 data gaps. When asked the same question, Claude reported: "Truly independent, peer-reviewed, or controlled original data specifically isolating the update's effect on Google Maps/local pack rankings is not yet available."

Gemini (42 prompts, Google Search with grounding): Found 2 explicit gaps and 6 queries where only limited or outdated research was cited. The most frequently cited domains were localdominator.co (5), youtube.com (6), whitespark.ca (6), reddit.com (5), and sterlingsky.ca (5).

Across all platforms, 476 unique domains were cited — none with original post-March 2026 local ranking data. The most-cited authority domains (BrightLocal, Whitespark, Sterling Sky) offer expert surveys and practice recommendations, not original ranking datasets. This study provides the first primary measurement.

Methodology

Scope: 11,500 Google Maps listings across 25 US metropolitan areas and 8 verticals (HVAC, Plumbing, Legal, Dental, Insurance, Restaurant, Auto Repair, Real Estate), using 23 search keywords.

Cities: Grand Rapids MI, Boise ID, Richmond VA, Des Moines IA, Knoxville TN, Chattanooga TN, Madison WI, Spokane WA, Akron OH, Dayton OH, Syracuse NY, Lexington KY, Reno NV, Fort Wayne IN, Greensboro NC, Worcester MA, Greenville SC, Savannah GA, Tallahassee FL, Baton Rouge LA, Tucson AZ, Wichita KS, Roanoke VA, Duluth MN, Amarillo TX.

Data source: DataForSEO Google Maps API, SERP API, Business Data API, and Labs Historical SERPs endpoint. Data collected April 7-8, 2026. Historical baseline from DataForSEO Labs snapshots (January-February 2026).

Unique businesses: 6,756 (deduplicated by Google CID across multiple keyword appearances).

Review data: Available for 1,514 of 11,500 listings (13.2% coverage). Review velocity and owner response rate findings are based on this subset and should be treated as directional.

GBP completeness: Derived from Maps listing data (website, phone, rating, review count, photos, category specificity). Direct GBP profile pulls returned limited results (21 of 1,003 succeeded) due to API matching constraints. Completeness scores exclude hours, description, and attribute data.

Keyword manipulation detection: Four-tier severity system. Only severity 2+ (keyword + city name, or multiple keywords) is reported as manipulation. Severity 1 (single keyword in name) is excluded from manipulation rates to reduce false positives from industries with natural service-term naming conventions.

LLM reconnaissance: 121 prompts across 4 platforms (Google Gemini 2.5 Flash with Search Grounding, Claude Sonnet 4.6 via Brave Search, Perplexity, ChatGPT). Conducted April 7-8, 2026.

Limitations: AI Overview detection via DataForSEO's organic SERP API returned zero positive results across 550 queries, which contradicts industry estimates of 7-16% for local queries. We cannot determine whether this reflects genuine rarity of AI Overviews for hyperlocal queries or API detection limitations, and we do not report AI Overview rates as a finding. Historical SERP comparison is based on 110 matched pairs of 500 attempted — results are directional, not comprehensive. GBP completeness analysis is constrained by limited direct profile data.

This study was triggered by ranking patterns observed while optimizing a client's Google Business Profile through the March 2026 core update, combined with practitioner reports from the r/localseo community (85,000+ members). The lead researcher maintains an active presence in r/localseo (7,500+ karma as MapsMedic).

Frequently Asked Questions

What This Means for Local Business Owners

If you run a local business that depends on Google to bring in customers, three things in this data matter more than anything else.

First, your review count is your moat. Businesses in the top 3 on Google Maps average 445 reviews — and in HVAC and plumbing, that number exceeds 800. If you have fewer than 100 reviews, closing that gap should be your single highest marketing priority.

Second, your business name on Google matters more than you think. Nearly 28% of top-3 dental listings contain keyword manipulation. If your competitors are stuffing their GBP names with keywords and city names, they may be gaining an unfair ranking advantage. You can report policy-violating names to Google — and our data says it's worth doing.

Third, the March 2026 update reshuffled the deck. 27.5% of local pack businesses changed. If your ranking dropped recently, you may be experiencing this churn directly. The businesses that survived had strong review bases and clean, complete profiles.

Download the Dataset

The complete anonymized dataset — 6,756 unique businesses with ranking position, review metrics, completeness scores, and keyword manipulation flags — is available as a free download.

Download: march-2026-study.csv (CC BY 4.0)

If you use this data in your own research or content, we ask that you link back to impious.io/research.

About This Study

This study was conducted by IMPIOUS LLC (impious.io), a local visibility research agency based in Grand Rapids, MI. Data was collected via DataForSEO APIs between April 7-8, 2026. LLM reconnaissance used Google Gemini 2.5 Flash, Claude Sonnet 4.6, Perplexity, and ChatGPT.

For methodology questions or custom analysis for your city or vertical: impy@impious.io.