Foster County Internet
Foster County, North Dakota has a Broadband Grade of A with an average download speed of 1000 Mbps across 3 ZIP codes. 100% of the county has fiber internet access, and the area averages 10 providers per ZIP code. Internet access is above average for the U.S.
ZIP Code Grades in Foster County
Fastest ZIP Codes in Foster County
| ZIP | Grade | Download | Providers | Fiber |
|---|---|---|---|---|
| 58421 | A | 1000 Mbps | 10 | Yes |
| 58443 | A | 1000 Mbps | 10 | Yes |
| 58445 | A | 1000 Mbps | 10 | Yes |
Slowest ZIP Codes in Foster County
| ZIP | Grade | Download | Providers | Fiber |
|---|---|---|---|---|
| 58421 | A | 1000 Mbps | 10 | Yes |
| 58443 | A | 1000 Mbps | 10 | Yes |
| 58445 | A | 1000 Mbps | 10 | Yes |
Frequently Asked Questions
What is the average internet speed in Foster County, North Dakota?
Foster County, North Dakota has an average maximum download speed of 1000 Mbps across 3 ZIP codes. The county received a Broadband Grade of A (100/100), which factors in download speed, provider competition, fiber availability, and upload speed. This meets the FCC broadband standard of 100 Mbps download.
How many internet providers are in Foster County?
Foster County has an average of 10 internet providers per ZIP code. 100% of ZIP codes in the county have fiber internet access. Having 3 or more providers typically leads to better prices and service quality through competition.
Is there fiber internet in Foster County?
100% of ZIP codes in Foster County, North Dakota have fiber internet available. Fiber provides the fastest and most reliable connections, typically 500 Mbps to 5 Gbps with symmetrical upload speeds. Fiber coverage in this county is above the national average.
What is the best ZIP code for internet in Foster County?
The best-connected ZIP code in Foster County is 58421 with a Broadband Grade of A, 1000 Mbps maximum download, and 10 providers. Fiber internet is available in this ZIP code.
See how your connection compares to Foster County's 1000 Mbps average.
The this entity record above pulls directly from the FCC Broadband Data Collection (BDC). What follows is the per-entity context — how this entity sits in the broader U.S. internet availability and broadband speed distribution and which underlying factors drive the headline numbers.
Every number on this page links back to the FCC Broadband Data Collection (BDC); the methodology page describes the inputs, refresh cadence, and known limitations of the underlying data product.
Practical use of this page is in combination with the comparison and ranking pages elsewhere on the site, which surface the same data for this entity’s peers within U.S. ZIPs, counties, and states. A single-entity reading without peer context can be misleading when an entity is an outlier on one axis but typical on another.
Source: FCC Broadband Data Collection, 2026.