Fontana Unified School District

It never has a ZIP Code to itself

At 1,193 homes to the square mile this is city territory, and district lines in a city follow streets. Fontana Unified covers 40 square miles in all — small enough that a single ZIP Code area can hold most of it, and several ZIP Codes can cut across it.

• Homes inside the boundary48,243
• Residents183,187
• ZIP Code areas it reaches9
• Where it is the only district0
• Where it shares with another district6
• Where it holds under half a percent3
• Land area40 square miles
• Homes per square mile1,193

The ZIP Code areas it reaches

The spread is the thing to notice. In 92335 this district holds 96% of the homes; in 92407 it holds no homes at all. Same district, opposite answers, and a lookup that names it without the share tells the second household the same thing as the first.

• ZIP Code 92335 · Fontana, California96% of the homes
• ZIP Code 92336 · Fontana, California60% of the homes
• ZIP Code 92337 · Fontana, California59% of the homes
• ZIP Code 92376 · Rialto, California8.9% of the homes
• ZIP Code 92316 · Bloomington, California7.0% of the homes
• ZIP Code 92358 · Lytle Creek, California5.9% of the homes
• ZIP Code 91739 · Rancho Cucamonga, California31 homes, under half a percent
• ZIP Code 92377 · Rialto, Californiano homes at all
• ZIP Code 92407 · San Bernardino, Californiano homes at all

What one name misses in the areas it leads

Fontana Unified is the largest district in 3 ZIP Code areas, and not one of them is wholly its own. Answer with its name alone and the answer misses 15,746 of the 61,382 homes those areas hold. That count is computed here from census blocks; the lookups that answer this question with a single name never print it.

Fontana Unified holds 15,917 of the 26,596 homes in ZIP Code 92336 · Fontana, California, so its name is right for most of the area and wrong for the rest: 10,679 homes with Etiwanda Elementary and Rialto Unified.

In ZIP Code 92337 · Fontana, California the split runs 5,619 to 3,972 and the larger part is Fontana Unified's: the rest is 3,972 homes with Colton Joint Unified.

Fontana Unified is not the name anyone would give for ZIP Code 92376 · Rialto, California — Rialto Unified leads it — and Fontana Unified holds 2,009 homes there all the same. Answer that area with one name and that is what it is wrong about.

ZIP Code 92316 · Bloomington, California is another area where Fontana Unified is present without being the answer: 542 of its 7,711 homes, behind Colton Joint Unified.

Who takes the other homes in its ZIP Codes

Fontana Unified runs kindergarten through grade 12 itself, so an address it holds sees no change of authority between grade school and high school. The districts listed below are the ones that take the other homes in the ZIP Code areas it shares — Rialto Unified, Chaffey Joint Union High and Etiwanda Elementary. They are neighbors on the same postal ground, not the next stop for its own students.

• Rialto Unified School District28,114 homes in 5 shared ZIP Code areas
• Chaffey Joint Union High School District22,238 homes in 3 shared ZIP Code areas
• Etiwanda Elementary School District22,232 homes in 2 shared ZIP Code areas
• San Bernardino City Unified School District18,607 homes in 1 shared ZIP Code area
• Colton Joint Unified School District12,236 homes in 3 shared ZIP Code areas
• Snowline Joint Unified School District3 homes in 1 shared ZIP Code area

Who it shares ZIP Codes with

Fontana Unified appears alongside a mix of district kinds — Colton Joint Unified, Rialto Unified, Chaffey Joint Union High and Etiwanda Elementary. Where the kinds differ, the two are not competing for the same address: one takes the lower grades and the other takes high school, and a household may be served by both.

• Colton Joint Unified School District3 shared ZIP areas
• Rialto Unified School District3 shared ZIP areas
• Chaffey Joint Union High School District2 shared ZIP areas
• Etiwanda Elementary School District1 shared ZIP area
• Snowline Joint Unified School District1 shared ZIP area

Where this district sits

• School districts in California996 of 1,788 ZIP areas split
• Every district with a page here260 districts listed

What to do next

Ask the district office to confirm your street address. A district settles that question on its own site: look for a school locator, a find my school tool, or an attendance zone map. Where there is none, ask the office itself.

A ZIP Code is a set of mail delivery routes, not a boundary: in 6 of the 9 ZIP Code areas Fontana Unified reaches, at least one other district holds a real share of the homes as well, and the line between them runs along streets. Only the district can say which side of that line an address is on.

This site links to no district website. None of the federal files it is built from publishes one, and a guessed address is worse than none. It is the district office, not a search engine, that settles an address.

If a house purchase depends on the answer, ask the district itself for written confirmation of that exact address. A listing is not a district record, and neither is this page.

What this cannot tell you

The homes were counted in the 2020 Census and the district lines are the 2026 boundary file. Nothing on this page adjusts one to the other. Where houses have been built or cleared since the count, a share here describes the place as it was counted rather than as it stands today, and in the fastest-growing ZIP Code areas that gap is the largest single source of error on this site.

A share on this page is a share of the homes in the ZIP Code area, not a probability for any particular address. Enrollment is decided by street address, and a district may run magnet, charter or choice programs that ignore the boundary entirely. If a decision depends on the answer, the district office is the only authority; this page shows what the federal boundary files say and when they were published.

A district boundary is not a school attendance zone. This site never says which school an address is assigned to: no current national dataset of attendance zones exists, and the district draws them itself. Nor is anything here endorsed or certified by the Census Bureau; we use their published files, and that is the whole of the relationship.

A ZIP Code is a set of mail delivery routes, not an area. What is mapped here is the Census Bureau's ZIP Code Tabulation Area, the closest published approximation to it. The two are not identical, and a handful of ZIP Codes used only for post office boxes or single buildings have no tabulation area at all.

Where these numbers come from

School district boundaries come from the Census Bureau's Census Geographic Relationship File, current 2026 vintage, which assigns every census block to a unified district or to an elementary and a secondary district. Homes and residents in each block come from the 2020 Census Redistricting Data (PL 94-171), H1_001 and P1_001. The ZIP Code areas come from the same Geographic Relationship File, block to ZIP Code Tabulation Area. District names and grade ranges come from the Census Gazetteer 2025, with 2020 for districts no longer listed.

The place name printed beside a ZIP Code comes from the Census 2020 ZIP Code Tabulation Area relationship files: place, county subdivision and county, taken 2026-09-06. It is a label rather than a measurement: the Census Bureau does not publish which post office a ZIP Code belongs to, so the place named is the one covering the most land inside the area, not the city the Postal Service prints on an envelope.

Everything else on this page — the shares, the counts of districts per ZIP, the comparison between the two grade bands, the rankings — is computed here from those files. The source publishes none of it. Snapshot taken 2026-09-03.