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Property profile & analytics

100 Borthwick Ave Portsmouth, NH 03801

  • Banks
  • 33,870 SF
  • 12.77 lot acres
Value Estimation
$8,865,000
Last Sale
Dec 03, 2024
$8,900,000
Location Intelligence
Property ID
US58-0559549
The Realmo ID is a unique identifier assigned to every property, incorporating country codes and precise geo-coordinates for 300x300-foot land blocks. It enables standardized data collection and seamless integration of disparate sources such as ownership, tax, title data and physical specifications. By aggregating current and historical records, the Realmo ID powers advanced analytics and delivers deep, verifiable insights for real estate professionals.

Current Use by Public Records

  • Money Management International (MMI) / Credit Counseling Service / Financial Planner

Property Details for 100 Borthwick Ave

Year built
1978
Construction
STEEL FRAME
Lot size
12.77 lot acres
Property size
33,870 SF
Zone code
OR
Property type
Banks
APN
PRSM M:0259 B:0015 L:
APU
PRSMM0259B0015L

Description

This exceptional two-story office building, located at 100 Borthwick Avenue in Portsmouth, New Hampshire, offers 47,745 square feet of premium executive office space. Currently, 42,827 square feet is available for lease, with flexible suite sizes ranging from a minimum of 1,748 square feet to a maximum contiguous space of 13,027 square feet. The building, constructed in 1978, sits on an expansive 8-acre lot and is zoned OR - Office Research, providing ample opportunity for a variety of businesses. The property boasts ample parking for tenants and employees, along with convenient elevator access for ease of movement between the two floors. The building is ideally situated in Portsmouth, NH, with the address being 100 Borthwick Ave, zip code 03801. This location offers excellent accessibility and visibility within Rockingham County. Multiple tenancy options are available, making this property suitable for businesses of various sizes and needs. Interested parties should inquire about the available spaces and lease terms. This is a rare opportunity to secure high-quality office space in a desirable Portsmouth location.

Value Estimation

by Realmo proprietary methodology Last update: July 3, 2025
  • AI approach

    CAP return
    Estimation
    Estimation
    $8,900,000
  • CAP approach

    CAP return
    Estimation
    6%
    $8,315,000
    6.5%
    $7,990,000
    7%
    $8,105,000
  • Comparable approach

    Method
    Estimation
    Relative Method
    $7,700,000
    Geo Method
    $10,010,000
  • Alternative Use

    Use
    Estimation
    Distribution
    $8,045,000
    Retail
    $8,385,000
    Mixed-Use
    $9,725,000
    Hospitality
    $8,190,000
    Educational
    $9,650,000
    Residential Income
    $8,015,000
    Energy
    $7,375,000
    Income-Based Land
    $7,735,000
    Food Service
    $10,205,000

Location Insight

  • Map
  • Local Demand
City
Portsmouth
County
Rockingham
State
New Hampshire
Longitude
-70.7938
Latitude
43.0602
CBSA code
14460
CBSA name
BOSTON-CAMBRIDGE-QUINCY, MA-NH METROPOLITAN STATISTICAL AREA

Property Tax & Assessments

Tax date
Tax Amount
Assessed Land Value
Assessed Improvement Value
Total Assessed Value
Applied Tax Rate
Land Market Value
Improvement Market Value
Total Market Value
2023
$116,073
$1,279,900
$5,916,200
$7,196,100
-
$0.00
$0.00
$0.00
More about this property
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