The Columbus Rat Report: where the rats are, and why.

Everything below is from City of Columbus code enforcement records, January 2, 2025 through August 31, 2026. Counts are complaints filed, not animals counted and not violations proven.

The city does not have a "rat" complaint type. It has record types, and a rodent complaint lands in one of them depending on where the animal is and who took the call. Two record types dominate, and neither is a pest type. "Weeds and Solid Waste" holds 981 of the 3,619 records. "Weeds" holds 876. Only 672 came in as "Occupied / Infestation", the type for an animal inside a dwelling. Another 488 are general housing code inspections.

More than half of all rodent complaints arrive as a yard complaint. The rat is usually the reason a neighbor finally called about the tall grass, not the subject of the call. That fits the text. Rat complaints track weeds complaints almost perfectly week to week, and trash complaints less well.

Rodent complaints are almost entirely resident-filed. Only 3 of 3,619 are inspector records or sweep notes, against 2,044 in the full dataset. There is no proactive-inspection floor under the rat map the way there is for weeds or vacant buildings. It is a pure map of who complained. People file on weekdays: Monday and Tuesday carry 41% of them, Saturday and Sunday 9%.

One artifact to know about. On January 13, 2026, 27 rodent records were filed in one day, 24 of them one-line "Occupied / Infestation" records in the Short North and the University District. That reads as a batch from a rental inspection, not 27 tenants calling on the same Tuesday. It is in the counts and flagged here.

Split the complaints by which word they use and two different problems appear. Of the complaints that say only "rat", 74% describe only the outside and 6% only the inside. Of the complaints that say only "mice", 34% describe only the inside and 29% only the outside. The 196 that say both are the worst houses, where the rats in the yard have become the rats in the kitchen.

Who gets blamed changes with the word. A neighbor’s trash or yard is blamed in 19% of all rodent complaints, and half of those say "rat". A landlord or management company is blamed in 13%, and 60% of those say "mice". The landlord / management rule fires on 12% of rodent complaints, three times its rate across all complaints. The pattern in the mouse complaints is consistent: a tenant reports mice, the landlord provides traps, the holes stay open, the tenant calls the city.

The vocabulary sorts the same way. Words that mark a rat complaint: alley, pile, porch, dumpster, trash, yard, debris, fence. Words that mark a mouse complaint: bathroom, sink, mold, unit, ceiling, kitchen, management, roach, walls, traps, maintenance, told, fixed. Mouse complaints are longer, and they travel with roaches: 318 rodent complaints also mention roaches, nearly all on the mouse side. Rat complaints travel with raccoons (151), snakes (79), possums (75), and skunks (44). The yard animals.

They have opposite seasons. Per 1,000 complaints of any kind, rat complaints peak in July at 27 and bottom out in February at 16. Mouse complaints peak in October, December, and January at 14 to 15, and bottom out in February and June at 8 to 9. Mice come inside when it gets cold. Rats are seen when people are outside. The share of rat complaints describing the animal inside also rises in winter: one in five from December through February, one in ten in early summer.

A caution on the labels. Complainants are not zoologists, and some "rats" are mice and the other way round. But the two groups differ so consistently on where, when, which building, and who is blamed that the words are tracking something real.

Three maps would tell it. The full set looks like the familiar shape: the Near East Side, Hilltop, Linden, the South Side. The "rat" map is tighter and follows the pre-1930 alley grid: South Hilltop, the Near East, Milo-Grogan and Linden along the numbered avenues, the South Side south of German Village. The "mice" map is diffuse and shifts outward: Northland, Wake Robin, the Far East Side, the Southwest, the apartment belt.

By rate, meaning rodent complaints per 1,000 complaints of any kind, the leader is not a place most people would name.

Wake Robin leads the city at 96 per 1,000, double the citywide 47, from 74 different addresses. It is a Northland district of garden-style complexes and townhomes, and a third of its rodent complaints are about mice. The text is dumpsters in shared parking lots, mice through patio-door gaps, and roaches and rodents at move-in. It is the clearest case in the data of a district with an outdoor rat problem and an indoor mouse problem at the same time.

Tamarack / Red Robin has the highest mouse share of any neighborhood, 56%, and a modest overall rate. It is the mouse capital.

The suburbs are not rat-free. Hayden Run, Hilliard, Far North / Polaris, and South of Refugee all sit above the city average per 1,000. Their absolute counts are small because their complaint volume is small, and their rodent complaints lean toward "rodent" and "mice" in new construction with no alleys. By raw volume the order is the familiar one: the Near East Side (405), South Hilltop (297), Far East / Eastland (227), the South Side (222), North Linden (221).

The alley is the tell. Group the neighborhoods by housing era and the overall rodent rate barely moves: 45 per 1,000 in the prewar core, 52 in the postwar inner ring, 50 in the outer suburbs. What changes is the animal and the setting. 15% of rodent complaints in the prewar core mention an alley. 4% do in the postwar ring. None do in the suburban belt. "Rat" complaints run 23 to 24 per 1,000 in prewar and postwar neighborhoods and 16 in the suburbs. "Mice" complaints run 9 per 1,000 in the core and 15 in the suburbs. The housing stock sorts its rodents.

Two ZIP codes stand out among the busy ones. Linden’s 43211 (64 per 1,000) and North Linden’s 43224 (63) have the highest rodent rates of any high-volume ZIP in the city.

A density clustering pass (reports within about 220 meters of each other, at least 8 to a cluster) puts 42% of the complaints into 73 clusters. Two are in a class of their own.

South Hilltop. A cluster centered on W Broad St, N Ogden Ave, Clarendon Ave, and S Harris Ave produced 199 rodent complaints from 144 different addresses, in every one of the 20 months. Summer 2025: 54 complaints. Summer 2026: 57.

The Near East Side. A cluster around E Livingston Ave, S 22nd St, S Ohio Ave, and Siebert St produced 151 complaints from 117 addresses in 19 of 20 months. Summer 2025: 49. Summer 2026: 40.

Two features define a real corridor. Sprawl: almost nobody reports twice. These are blocks where rats are a condition of the block, not a property, and moving across the street does not help. Persistence: both corridors were active nearly every month and both came back in summer 2026 at summer 2025 size. Nothing else in the city is half their size.

The next tier: E 18th, E 17th, and E 21st Ave in Milo-Grogan (63 complaints, 39 addresses). E Jenkins, E Hinman, and Sheldon Ave on the South Side (60 from 37, and growing: 12 in summer 2025 to 21 in summer 2026). N 4th St, Summit St, and E 9th Ave in the Short North and Italian Village (59 from 51, and growing from 10 to 18). E Weber Rd, Manchester Ave, and Aberdeen Ave in North Linden (57 from 40).

A few clusters are not corridors at all but one or two properties with a persistent reporter. The sprawl column separates them from the real thing: a cluster with 16 reports from 4 addresses is a feud, not a corridor. This report does not name those.

Same months, January through August, 2025 against 2026. Citywide, rodent complaints rose 26%. The growth was not in the old corridors.

Northland went from 28 to 63. Clintonville from 32 to 55. The Hilltop core from 43 to 72. The Near East Side, South Hilltop, Milo-Grogan, and Linden held flat or fell. Split by animal, "rat" complaints in Clintonville doubled (16 to 33) and in the Hilltop core went from 26 to 44. "Mice" complaints grew most in the Far East (29 to 38) and North Linden (15 to 19), and fell on the South Side (12 to 6).

Two streets to watch: N 4th St (4 complaints in 2025, 12 in 2026) and Karl Rd (3 to 13). Neither registered a year ago.

Rodents are also taking a growing share of everything the city hears. 41 rodent complaints per 1,000 in the first half of 2025, 48 in the second half, 50 in the first half of 2026, 53 in the summer. Summer 2025 was 50 per 1,000. Summer 2026 was 55. Rats are outgrowing the general rise in complaints.

The question that prompted this section was whether garden-style apartment complexes have the worst rat problems. The complaint text cannot answer it directly: "slab" appears once in 3,619 complaints and "garden-style" never. But the site’s spatial complex detection, which groups addresses within about 500 feet when both sides are multi-unit, can stand in for building type.

The answer is no, with a twist. Big complexes have the lowest rodent-complaint rate of any building type. What they have is a mouse problem. The mouse share rises steadily with building size, so does the share describing the animal inside, and so does the share naming the landlord. The rat, as a complaint, belongs to houses and small multi-family buildings with yards, sheds, detached garages, and alleys. The mouse belongs to apartments.

The peak rodent rate is at the 3-to-5 address cluster: the doubles, the four-unit conversions, the small rental rows of the prewar neighborhoods. That is the housing at the center of the two big corridors.

A caution on the low number for big complexes. These are complaints, not animals. A large complex usually has an on-site office, a maintenance staff, and a pest-control contract, so a mouse in a unit there tends to get handled inside the building and never reaches the city. A small landlord often has none of that. People generally call the city when the person responsible is not helping, which is why the share naming the landlord climbs with building size even as the overall rate falls. The rate for big complexes is a count of the problems that got past management, not a count of the problems.

The exception is the Northland garden-apartment belt. Wake Robin leads the city on rate and Tamarack leads on mouse share, and the two big complexes with the highest rodent share of their own complaints are both apartment complexes, one in South Hilltop and one in Wake Robin. So the hypothesis was right about which complexes and wrong about which animal. Those complexes have mice inside more than rats outside.

Only 57 addresses in the city have four or more rodent complaints. 82% have one. Rats are not a property phenomenon in this data. They are a block phenomenon.

For every rodent complaint, look 300 feet in every direction and ask what other kinds of complaints sit there, then compare with a random sample of all complaints.

Vacant houses and encampments get blamed in the text, in 6% and 5% of complaints, but the geography does not support the blame. A rodent complaint is no more likely than any other complaint to sit near one. Restaurants come out the other way: rats are less likely near a restaurant complaint than chance. The only clean signals are hoarding and backyard chickens, both of which are food and shelter on a residential lot.

Rats do cluster with each other. 48.5% of rodent-complaint addresses have another rodent-complaint address within 300 feet, against 39.5% for a random address. That is the corridor effect. Once one yard on a block has rats, the neighbors see them too.

People wait. 335 rodent complaints say how long the problem has lasted. The median is 150 days, and 27% say a year or more. "For years" appears 144 times. "First time" or "never seen before" appears 15 times. Rat complaints have a median stated duration of 180 days, mouse complaints 90. Another 359 say some version of "I have reported this before."

Rats chew cars. 253 complaints (7%) mention wires, an engine, or a car, mostly rats nesting under hoods in alleys and driveways. One complainant reports two thousand dollars in chewed wiring. The alley-parked car is where a yard rat becomes an expensive rat. More on that.

The harm is real and mostly on the mouse side. 277 complaints mention sickness or disease. 173 mention children. 150 mention the fridge or food. 98 mention dead rats. 49 describe an animal in a bed. 14 describe a bite. The bites and the beds are the mouse complaints.

What people ask for. 146 complaints mention an exterminator, 88 mention traps, 56 bait or poison, 64 the health department. The pattern at rentals: the landlord provides traps, the tenant wants the holes closed. The pattern at owner-occupied houses: the complainant has already hired someone and wants the city to make the neighbor do the same.

"Please." 39% of rodent complaints contain the word, against 21% of all complaints. 64 say "please help," "desperate," or "begging." 21 ask to stay anonymous. 15 mention retaliation. Rat complaints are the politest, most pleading category in the dataset, and almost all of them are written by the person who has to live next to the rats.

Short excerpts, lightly trimmed. Names, addresses, and unit numbers are removed, and nothing here identifies a person or a property.

• The alley: "My neighbors do not take garbage to the alley for collection. As a result we are seeing rodents on our property: rats, raccoons, and opossums."
• The neighbor’s yard: "Home and yard are infested with rats. Coming into my yard, going into the neighbor’s yard, digging large rat holes in the fence."
• Chickens: "At least seven chickens, feed all over the backyard. It stinks and is drawing rats into our yard. I have small kids and a small dog."
• Burrows: "Rats have burrowed under the bushes next to the dumpsters. They are larger than my pomeranian."
• The landlord, mice: "Home is infested with mice. Have told the landlord and he gives mouse traps but it has not solved the issue. There are holes in the home to let rodents and roaches in."
• The car: "We have seen rats in our cars and they have chewed through the wires. We had to pay over two thousand dollars to get it fixed."
• The tenant who left: "Tenants moved out and left a huge pile of trash in the back, spilling into the alley. Concerns with huge rats, opossums and raccoons being seen."

Averaging each calendar month over the two years, some neighborhoods have a rat season and some have rats all year.

Year-round: Wake Robin, Franklinton, the Far East Side, and the Near East Side keep 40 to 60% of their summer rate through the winter. The Near East averages 16 rodent complaints in January against 30 in July. Wake Robin’s busiest month after July is December.

Summer only: Clintonville (one or two a month in winter, ten in July), Northland (one to four against eleven in June), Lincoln Village, Berwick, and the Hilltop core. Places where rats are seen in the yard in summer and forgotten in winter.

Fall peak: Linden’s busiest month is September. North Linden stays high through October. That is the harvest pattern: rats move when the yards get cleaned up and the weather turns.

• Rat in the yard, the alley, or a neighbor’s lot: report the condition that draws it, not the animal. What to say so an inspector comes.
• Mice inside a rental: the fix is sealed holes, not traps, and the landlord’s duty starts when you tell them in writing. Who has to fix it, and what the records show.
• Not sure which one you have? How to tell, and why the wrong word sends the wrong inspector.
• Rats in the car: what is happening and what the city can and cannot do.
• Looking at an address: the numbers on this page are neighborhood averages, and 82% of rodent addresses were reported once. Check the block, not the average.

• Corpus. A record is included if the pipeline’s rats rule fires (it matches rat, rats, mice, mouse, and rodent) or the complaint text matches those words directly. The rule and the text agree on 99.7% of the set. A handful of non-animal uses of "rat" remain.
• Rats versus mice is by word choice. The 1,385 "rodent only" records are mostly weeds and trash complaints that cite rodents as a risk. They are in the corpus because the city and the pipeline treat them as rodent records. A sightings-only count is about 2,200.
• Neighborhoods are the site’s bounding boxes, applied in list order. 13% of the corpus falls outside every box. The housing-era grouping is an editorial assignment of those boxes, not parcel data. Rates per 1,000 use each neighborhood’s total complaint count as the denominator, so a neighborhood with few complaints of any kind can rank high on a small base.
• Clusters are DBSCAN over latitude and longitude with an epsilon of about 220 meters and a minimum of 8 records. Cluster names are the most frequent streets inside the cluster. Low-sprawl clusters, meaning few addresses relative to reports, are treated as single-reporter situations and not named.
• Building size is the pipeline’s spatial complex detection, not parcel or construction data. Construction year and building style are not in the text and could not be tested.
• Proximity lifts compare rodent complaints with a 12,000-record random sample of all complaints, against address-deduplicated targets, within 300 feet.
• The January 13, 2026 batch is treated as an inspection batch, not a tenant event.
• Suppressed addresses. Four chronic single-reporter addresses are excluded from the site’s data before all counts. Complainant, tenant, and landlord names were not used and are not quoted.
• No weather data was joined. The seasonal claims rest on the complaint calendar alone.
• This is a snapshot. The numbers on this page are fixed to the data through August 2026 and will be refreshed each September. The live rats and mice page recomputes its numbers every time the data updates.
• Corrections. None yet. Corrections will be listed here with the date.