| Index | Portsmouth | New Hampshire | National |
| Average Test Scores | 75% | 52% | 48% |
| Student/Teacher ratio | 13:1 | 13:1 | 16:1 |
| Total public schools | 6 | 234 | 79,221 |
| Total private schools | 1 | 144 | 24,874 |
| Total post-secondary schools | 3 | 40 | 7,963 |
| Index | Portsmouth | New Hampshire | National |
| Completed 8th grade | 93.9% | 89.5% | 84.3% |
| Completed high school | 93.4% | 88.4% | 83.0% |
| Completed some college | 79.6% | 64.2% | 59.4% |
| Completed associate degree | 65.9% | 45.3% | 38.5% |
| Completed bachelors | 57.6% | 35.5% | 30.3% |
| Completed masters | 21.4% | 13.4% | 11.5% |
| Completed professional degree | 5.3% | 3.3% | 3.3% |
| Completed doctorate | 2.7% | 1.4% | 1.3% |
There are a total of 6 public schools, 1 private schools and 3 post-secondary schools in Portsmouth. Using the proficiency score averages, the average test scores for Portsmouth, NH schools is 75%. The average student to teacher ratio is 13:1. In Portsmouth, NH, an average of 93.9% of students have completed 8th grade and an average of 93.4% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Durham, NH | 12,016 | 76% | 57.8% |
| Hampton, NH | 10,002 | 70% | 45.1% |
| York Harbor, ME | 3,484 | 66% | 36.5% |
| Kittery Point, ME | 1,034 | 65% | 34.4% |
| Cape Neddick, ME | 2,563 | 65% | 34.4% |
| Portsmouth, NH | 21,418 | 75% | 55.8% |
| City | Population | Avg. Test Scores | National Avg. |
| North Bellmore, NY | 21,422 | 57% | 18.8% |
| Mukilteo, WA | 21,414 | 69% | 43.6% |
| Duarte, CA | 21,399 | 40% | 16.1% |
| Bear, DE | 21,397 | 48% | 0.7% |
| North Plainfield, NJ | 21,445 | 31% | 35.2% |
| Portsmouth, NH | 21,418 | 75% | 55.8% |
Here are the best places to live in New Hampshire
Most Dangerous States In The US
See the best places to live in Portsmouth
These are the largest cities in New Hampshire