The county council has it's HQ in Lincoln the 'county town'.

Lincolnshire County Council

Marsh Yard Coastal car park has 2 spaces for horseboxes/larger vehicles.
Byelaws prohibit overnight parking (between 10pm and 6am) at all coastal car parks.

Whisby Nature Reserve (to the west of Lincoln) has a car park, owned by North Kesteven District Council. The usual restrictions apply. There is no size information but coaches can park here so no height restrictions.

City of Lincoln Council states
If your motorhome will fit in a standard parking bay (2.5m x 5m), and you wish to park in our car parks, you will need to purchase a pay and display ticket as normal.
The Lawn ( LN1 3BU) offers access for motorhome users, with bays backing onto grass for longer vehicles to reverse into. Please note that whilst motorhomes may park overnight sleeping in your vehicle is not permitted.

Waitrose Park and Ride.
Park for free and save the hassle of finding a parking space by using Lincoln Park & Ride when arriving by car.
The Park & Ride runs Monday - Saturday (no service on Bank Holidays) from Waitrose on Searby Road, Lincoln, LN2 4DS, with a bus provided every 15 minutes from 7am (8am on Saturday) with the last return bus departing at 6:20pm (services at peak times early and late in the day may vary).
Parking at Waitrose is free. Return tickets are available on the bus are at a cost of:
Adults: £2.50
Accompanied children: free.

East Lindsey District Council - Skegness, Ingoldmills, Chapel St Leonards, Sutton on Sea, Mablethorpe, Horncastle, Woodhall Spa.

'Oversized vehicles - Are welcomed in our car parks, where space permits. Please ensure that you purchase a machine ticket for each full or part space occupied. Overnight occupation of vehicles is not permitted.'

OS Map Landranger 122: Explorer Louth and Mablethorpe 283
The Seal Sanctuary has a pay on entry car park with no marked bays.
Just off the Main Street there is a coach and motorhome park called Seacroft. It is actually marked for motorhomes so well done Mablethorpe.

Seacroft, Quebec Road, Queens Park Main and Queens Park South are some car parks in Mablethorpes without height barriers.

OS Map Landranger 122: Explorer Skegness, Alford and Spilsby 274, Boston 261
Parking restrictions end on September 30th so there may be some on road parking after this date.
In Richmond Drive (PE25 3PG) there is a coach and motorhome park. It is behind the railway and bus stations and is marked for coaches and motorhomes.

Gibraltar Point
There are 2 car parks here, both pay and display.. Neither has a height restriction or bay marks. It is about 3 miles into Skegness.

Sutton on Sea
OS Map Landranger 122: Explorer Louth and Mablethorpe 283
At Huttoft Car Terrace there is a lovely car park with plenty of space for motor homes and all by the sea. The prom from here goes all the way to Mablethorpe a distance of about 6 miles. 'The county council has begun the process with a view to issuing summons against people parking overnight at Huttoft Car Terrace, situated between Mablethorpe and Skegness.'(2017)
At Sandilands, next to the golf course there is a small car park which takes motor homes. There is no height or width barriers.

North Kesteven - Sleaford, North Hykeham.

Sleaford market takes place every Monday, Friday and Saturday.

Sleaford - East Gate - 172 spaces no height information.
Sleaford - East Banks - 137 spaces no height information.
Sleaford - Grantham Road - 100 spaces no height information.

South Kesteven District Council - Grantham, Stamford, Bourne, Market Deeping.

Grantham - Belton House NG32 2LW - large car park without height barriers. Mostly grass so watchout in wet weather. The drive ways have a plastics undersurface to the grass but the parking doesn't. So if you have non-slip mats it might be advisable to use them. Belton has the largest adventure playground for children in the NT network and is pretty spectacular but also is a lovely house and gardens with plenty of walking paths available. There also is an indoor play area for children which is pretty good and you can have coffee and cake while the young ones play.

Grantham - All car parks in Grantham have a height barrier.


OS Map Landranger 130: Explorer Rutland Water 234
4 council run car parks don't have height barriers. North St PE9 1EG, Scotgate PE9 2YE, St Leonards Street PE9 2HX and Bath Row PE9 2WE all have spaces for motorhomes.
Stamford is widely regarded as one of the finest stone towns in England. The pretty facades of the town are favourites with film and television producers - Stamford was used as Meryton in the 2005 Pride & Prejudice film and has also appeared in Middlemarch, The Da Vinci Code and the Golden Bowl.  It’s no wonder that visitors come from far and wide to experience Stamford’s charm, character and outstanding shopping and restaurants.

Burghley Street and South Street do not have height barriers.

Market Deeping
Halfleet does not have height barriers.

North Lincolnshire Council

Scunthorpe, Brigg, Barton-upon-Humber.

There is no information on the website regarding height restrictions.

Scunthorpe - Dunstall Street DN15 6LD - 181 spaces.
Scunthorpe - Carlton Street DN15 6TA - 192 spaces.
Brigg - Old Courts Road DN20 8JD - 254 spaces.

North East Lincolnshire Council

Meridian Line (this is THE Meridian Line from Greenwich) has a free carpark (Meridian Road DN35 0AR) with no bays and no height restrictions with a lovely view over the River Humber.

Grimsby, Cleethorpes.

Car parks are shown on a map (opens as .pdf) for each town but giving no further information about the car park. No 5 on the map of Grimsby is a multi storey.

Cleethorpes South car parks.
Cleethorpes North car parks. The two promenade car parks are easily the biggest.