Boat Dock Lines for Beginners: 12 Questions Answered

As a boat owner, you don’t have to be an expert on dock lines, but you should know how they work and a few best practices for docking at the marina. I’ve seen many boat owners struggle to tie up their boat to a dock, and it that’s you…don’t worry.

In the post, I’ll cover 12 common questions for beginners so you’ll know what you need to know about dock lines.

1. What type of dock lines should you choose?

If buying dock lines for the first time, determine if your lines will be permanent or temporary.  Will you be docking in your permanent location every time or not?

For example, if you will be docking in the same place every time, you don’t need a bunch of extra line getting in the way. You should ensure your lines are the exact length you need as well as having loops on both ends of the line can make for a safe and tidy dock.

If you are willing to put in a little bit of sweat equity, consider splicing your own lines to create loops exactly where you need them. These splicing fids are a great tool for most rope sizes and their stainless steel design makes for easy work.

2. How many dock lines do you need for a boat?

All boats will need a minimum of four dock lines, regardless of size. If you are only docking at home you will need at least one bow line and one stern line.

3. What’s the purpose of bow and stern lines?

Bow and stern lines on a boat prevent either end of your boat from pulling away from the dock.

Depending on your dock, you may need additional lines for your bow or stern. Factors like exposure to elements (such as wind or currents) should also be considered.

Since you may have to dock on either side of a dock when traveling, it will be less chaotic if you have two bow lines and two stern lines. If you travel often, it’s a good idea to add more lines than two per side for convenience.

4. What is a boat’s spring line?

Spring lines refer to lines located in the middle of the boat and cross on a shallow diagonal. Spring lines are generally categorized into two types: forward spring lines and after (or aft) spring lines.

  • After spring lines keep the boat from moving backwards (towards the stern) when docked
  • Forward spring line: keeps the boat from moving forward (towards the bow) when docked

Bow lines and stern lines help to line up a boat and prevent side-to-side movement, while spring lines prevent forward and backward movement along the dock.

5. How thick should dock lines be?

The standard diameter for dock lines is ⅛ of an inch for every 9 ft of boat.

Dock lines at a minimum should be ⅜ of an inch thick regardless of boat size. Generally the larger the rope the easier it is to handle, so many boaters tend to round up when selecting lines.

6. How long should dock lines be?

As a general rule, bow and stern lines should be at least ⅔ the length of the boat. For example, if you have a 20 ft boat your lines should be approximately 13 ft.

If you are docking at home you can measure your current lines to get an accurate length for each line.

Spring lines should be the length of your boat but this is something you can customize if you will only be docking at home.

You make your boat more secure if you adjust the clean location and length of your dock lines. Be sure to place your cleats and lines with an opening for boarding where there are no tripping hazards.

7. Why is nylon is the best dock line material?

The go-to material for dock lines is nylon due to its ability to stretch and durability. Nylon lines are also the perfect weight for tossing should the occasion arise, and are relatively inexpensive.

Polypropylene ropes are great for when you need a rope to float, but they deteriorate quickly in the sun.

8. What type of dock line braids are there?

For the most part, there are three types of braids for nylon dock lines.

  • Three-strand twisted. This is the most affordable nylon line and the easiest to splice. It is composed of no inner core but simply three nylon lines twisted together.
  • Braided. This is composed of a smooth inner core and a braided sheath. It is easy to handle.
  • Double braided. The double braided line type is braided on both the inside and the outside of the rope. For this reason, they will be the most durable.

9. Does dock line color matter?

Dock line colors do not matter, it’s simply a matter of personal preference as opposed to any type of color-coding system.

Consider that white lines will show dirt and dark lines will be subject to UV damage and fading.

Some people choose to use one color for the bow and stern lines and another color for the spring lines. This can simplify communication during docking and undocking.

10. How long do dock lines last?

Dock lines will usually need to be replaced every 3-5 years depending on your setup and exposure to the elements.

Rain, mildew, and salt water can take their toll on lines. Eliminating buildup as it appears can help improve the lifespan of your lines.

11. How do you clean dock lines?

The best way to clean dock lines is to let them soak in a dish detergent like Dawn overnight. You can then place them in a mesh bag and wash them with a small amount of detergent and fabric softener before rinsing.

Depending on how dirty your dock lines are, you may want to use an older washing machine; dock lines won’t harm your washing machine unless absolutely filthy or oil-stained. It’s a good idea to wipe the drum out afterward or use a washing machine cleaner to be safe.

To dry dock lines, hang them, but do not place them in a dryer because they can degrade under high heat.

Vinegar can also help break down mold and mildew.

Inspect your dock lines regularly

During your annual cleaning, lines should be inspected for chafing or tearing. There are solutions for preventing chafing. Rubber sleeves or chafe guards like these are designed to slip over your dock lines and will reduce wear and tear over time.

12. Can you buy custom boat dock lines?

Yes. Boat dock lines come in all shapes and sizes, and can even be personalized to the length you need (so you don’t have to splice them) online at places like

You can personalize your dock lines further by having the maker attach a label to match the name of your boat; these customizations can be made on websites like or


While docking your boat is really a craft that is honed over time, assessing the condition of your lines and preparing for every potential situation will ensure your boat is safe and secure.

Keeping the dock clean with coiled lines or draping them over the cleat will prevent tripping and also make you look like a seasoned boater!

While you’re at it, be sure to check out the post I wrote on Dock Cleats 101, for everything you need to know on that front 🙂

This post was updated on July 5, 2022.

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