How far is Loudon, NH from Portsmouth, NH?

The driving distance from Loudon, NH to Portsmouth, NH is about 42.7 miles (68.7 km), with a travel time of about 01h 01m by car.

  • The straight-line flight distance is about 38.5 miles (62 km).
  • For a round trip, plan for roughly 02h 02m of driving time before adding stops, traffic, or weather delays.
  • A comfortable departure window is usually 8:00 AM to 10:00 AM EDT.
Trip Tools

Reverse, save, or send this route

This route works well as a day trip with time at the destination. Copy the route link, send it to another device, or print a clean version before you head out.

Reverse Route
Quick Snapshot
Road
42.71 mi
01h 01m
Flight
38.55 mi
62.04 km direct

This route works well as a day trip with time at the destination.

Learn Distance

Choose another destination from Loudon.

Flight Distance

Direct air line
38.55 mi
Kilometers
62.04 km
Flight Time
00h 04m

Driving Distance

Road route
42.71 mi
Kilometers
68.73 km
Drive Time
01h 01m

Gas Cost Calculator

Leave and Arrive Planner

Pick a departure time to see your estimated arrival and same-day return window.

Drive time stays fixed at 01h 01m.

Arrival Snapshot
Arrive in Portsmouth
Thu, Oct 15, 1:59 PM EDT
Return by in Loudon
Thu, Oct 15, 3:01 PM EDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave Loudon
2026-10-15T12:58
Arrive Portsmouth
Thu, Oct 15, 1:59 PM EDT
Route Timing
01h 01m
One way by road
Best Departure Window
8:00 AM to 10:00 AM EDT
Aim for a morning departure
Arrive between
9:01 AM to 11:01 AM EDT

A morning start gives you useful time at the destination and keeps the return out of the late evening.

Leave by
4:28 PM EDT
Keeps a same-day return open with about 03h 00m at the destination.
Back in Loudon
9:30 PM EDT
Morning start is best

You are leaving earlier than the recommended window, which gives you extra margin for breaks and traffic.

Halfway Point

A useful midpoint for breaks, coffee, or meeting in the middle.

Mid-route stop
Northwood
NH

Place in New Hampshire, United States

From Loudon
21.3 mi
00h 30m
To Portsmouth
21.4 mi
00h 30m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
59ยฐF
This Afternoon

Sunny

Starts
Thu, Oct 15 12:00 PM EDT
Wind
5 mph NW
Destination
Portsmouth Weather
NH
Live fallback forecast
60ยฐF
Thursday
Using Greenland as the closest live forecast in the Rockingham County weather hub.

Sunny

Starts
Thu, Oct 15 6:00 AM EDT
Wind
0 to 5 mph NW

Driving Route Map

The map below follows the saved road route between Loudon and Portsmouth.

Turn-by-Turn Driving Directions

Step-by-step road directions between Loudon and Portsmouth.

  1. 1

    Start on South Village Road

    1.3 km ยท 2 min ยท South Village Road

  2. 2

    Continue on Chichester Road

    1.7 mi ยท 4 min ยท Chichester Road

  3. 3

    Continue on King Road

    1.4 mi ยท 4 min ยท King Road

  4. 4

    At the end of the road, turn left onto Dover Road

    3.1 mi ยท 5 min ยท Dover Road

  5. 5

    Enter the roundabout and take exit 2 toward Epsom Circle

    76 m ยท 6 sec ยท Dover Road

  6. 6

    Exit the rotary onto Dover Road

    4.3 mi ยท 7 min ยท Dover Road

  7. 7

    Continue on First New Hampshire Turnpike

    7.8 mi ยท 13 min ยท First New Hampshire Turnpike

  8. 8

    Continue on Old Turnpike Road

    5.1 mi ยท 7 min ยท Old Turnpike Road

  9. 9

    Continue on Old Concord Turnpike

    1.8 mi ยท 3 min ยท Old Concord Turnpike

  10. 10

    Continue on Concord Road

    2565 ft ยท 56 sec ยท Concord Road

  11. 11

    Enter the roundabout and take exit 2 toward Lee Circle

    50 m ยท 5 sec ยท Concord Road

  12. 12

    Exit the rotary onto Concord Road

    8.9 mi ยท 14 min ยท Concord Road

  13. 13

    Continue on Scammell Bridge

    1132 ft ยท 28 sec ยท Scammell Bridge

  14. 14

    Continue on Boston Harbor Road

    812 ft ยท 22 sec ยท Boston Harbor Road

  15. 15

    Enter the roundabout and take exit 2 toward the route

    54 m ยท 4 sec

  16. 16

    Exit the roundabout

    684 ft ยท 17 sec

  17. 17

    Take the exit slight right

    2827 ft ยท 1 min

  18. 18

    Merge slight left onto Spaulding Turnpike

    3.5 mi ยท 5 min ยท Spaulding Turnpike

  19. 19

    Take the exit slight left toward I 95 North

    1.5 km ยท 2 min

  20. 20

    Enter the roundabout and take exit 3 toward Portsmouth Traffic Circle

    692 ft ยท 20 sec

  21. 21

    Exit the rotary onto US 1 Bypass North: Portsmouth, Woodbury Avenue

    1.6 km ยท 2 min

  22. 22

    Turn left onto Submarine Way

    566 ft ยท 18 sec ยท Submarine Way

  23. 23

    Turn right onto Market Street

    1 km ยท 2 min ยท Market Street

  24. 24

    At the end of the road, turn right onto Congress Street

    16 m ยท 1 sec ยท Congress Street

  25. 25

    Arrive at your destination

    0 m ยท 1 sec ยท Congress Street

Car Route Details

A richer read on the saved driving route between Loudon and Portsmouth.

OSRM road route
Drive Character

Turn-heavy local drive

The route has frequent decision points for its length, so lane choice and turn timing will matter more than cruising speed.

Directions
25 steps
16 turns on the saved route
Ramps & Exits
11
1 merges, 10 ramps or exits
Navigation Density
58.5 / 100 mi
Decision points by distance
Main Roads
Concord Road
9.35 mi ยท 22%
First New Hampshire Turnpike
7.78 mi ยท 18%
Dover Road
7.42 mi ยท 17%
Old Turnpike Road
5.06 mi ยท 12%
Spaulding Turnpike
3.53 mi ยท 8%
Old Concord Turnpike
1.84 mi ยท 4%
Longest Stretch

Concord Road

Exit the rotary onto Concord Road

8.85 mi ยท 00h 14m

Route Summary

A quick read on whether this route feels easy, ambitious, or worth planning around.

Trip Read

A comfortable day-trip route

This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.

Drive Time
01h 01m
Day trip friendly
Same-Day Return
02h 02m
Round-trip wheel time
Road vs Air
+4.2 mi
38.5 mi direct line
Halfway Stop
Northwood
00h 30m from Loudon
Leave By
4:28 PM EDT
Morning start is best
Weather Watch

Sunny leaving Loudon and Sunny near Portsmouth.

Trip Questions

Direct answers travelers usually want before committing to the drive.

How long does it take to drive from Loudon to Portsmouth?

The road trip is about 42.7 miles (68.7 km) and usually takes 01h 01m in normal driving conditions.

Is this a same-day trip or an overnight route?

This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.

What is the halfway point on this route?

Northwood is a useful midpoint, sitting about 21.3 miles from Loudon and 21.4 miles from Portsmouth.

How much longer is the road route than the straight-line distance?

The direct path is about 38.5 miles (62 km), while the road route adds roughly 4.2 extra miles because roads do not follow the straight air line.

When is the best time to leave for this route?

A good departure window is usually 8:00 AM to 10:00 AM EDT. If you want a more comfortable same-day return, try to leave by 4:28 PM EDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $6.48 one way or $12.97 round trip. Estimated CO2 is about 13.4 kg one way.

What should you check before leaving?

Before you leave, expect Sunny around Loudon and Sunny near Portsmouth.

Stop Ideas Near Northwood

Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.

Mid-route Guidance
Local place coverage is thin around Northwood, so nearby transit and meeting points are shown instead.
Reviewed stop coverage is still thin around this midpoint, so practical transit waypoints are shown on the right.

Transit and Meeting Points

Useful pickup, handoff, or rendezvous points close to Northwood.

RAIL

Durhamโ€“UNH station

18 mi away
3 Depot Road
RAIL

Dover Transportation Center

22 mi away
33 Chestnut St.
RAIL

Exeter station

28 mi away
60 Lincoln Street
BUS

Concord, New Hampshire

31 mi away
30 Stickney Ave.

Flight Path Map

This map shows the direct air route between Loudon and Portsmouth. Straight-line distance: 38.55 mi (62.04 km).

Loudon

#1 Loudon

Town of the United States

Population5,697
Coordinates43.2856400, -71.4672900
Altitude116
CountryUnited States
Portsmouth

#2 Portsmouth

City in Rockingham County, New Hampshire, United States

Population21,557
Coordinates43.0770400, -70.7576600
Altitude6
CountryUnited States
Start: South Village Road (-71.467298, 43.285635)
End: Congress Street (-70.757617, 43.077054)

Estimated Travel Time

Distance: 69 km by road

SpeedTime
30 mph (48.3 km/h)01h 25m
40 mph (64.37 km/h)01h 04m
50 mph (80.47 km/h)00h 51m
60 mph (96.56 km/h)00h 42m
70 mph (112.65 km/h)00h 36m
80 mph (129 km/h)00h 31m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
1.51 gal
5.7 L ยท about $6.48
Round trip
$12.97
3.02 gal ยท 11.4 L
Estimated CO2
13.4 kg one way
Round trip: 26.8 kg / 59 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $4.29 $6.48 $12.97
Mid-grade $4.88 $7.37 $14.75
Premium $5.34 $8.06 $16.12
Diesel $6.35 $9.59 $19.18

Assumes 8.3 L/100 km (about 28.3 MPG). CO2 is an estimate and varies by vehicle, fuel blend, traffic, and terrain.

Prices in New Hampshire ยท Oct 15, 2026

There is no time difference between Loudon and Portsmouth. The current time is 12:58:45.

Distance to Other Cities

How did we calculate? Place names are translated into coordinates. The Haversine formula calculates straight-line distance; driving distance uses road network data.