Offshore Passage Provisioning: The Complete Checklist for Blue-Water Sailors

Provisioning an offshore passage is different from any other kind of trip planning. The variables are unique: you can't resupply mid-passage, conditions affect what you can cook, seasickness affects what crew can eat, and the duration is uncertain by days or weeks depending on wind. A well-provisioned boat is comfortable and safe. A poorly provisioned boat becomes a morale and safety problem.

The Calculation Framework

How long will you be at sea? Take your estimated passage time and add 50% as a buffer. A 10-day Atlantic crossing should be provisioned for 15 days.

How many crew, and what will they eat? Simple question with complex answers. Who gets seasick? Who is vegetarian? Who is the cook? Account for reduced appetite in the first 1–3 days as everyone finds their sea legs.

How will you cook? In heavy weather, cooking at a stove is dangerous. Plan for meals that can be prepared and eaten with one hand or in a cup. Eat hot food while you can; plan simple cold food for rough conditions.

Water

Water is the most critical provision. The minimum recommendation: 1.5 liters per person per day for drinking, plus additional for cooking. A crew of three on a 15-day provision plan needs: 3 × 1.5 × 15 = 67.5 liters minimum for drinking alone.

Factor in:

• Cooking water: roughly 1 liter/meal
• Emergency reserve: 20% above calculated needs
• Watermaker backup plan if your watermaker fails

If your boat has a watermaker, maintain your water tanks full anyway. Watermakers fail. Membranes foul. Power outages happen.

Food Categories

High Priority: Calories Under Any Conditions

These are the foods that can be eaten in rough conditions, by a seasick crew, without cooking:

• Crackers (multiple types, different flavors)
• Peanut butter and nut butters
• Energy bars and meal replacement bars
• Dried fruit, nuts, seeds
• Canned fish (tuna, sardines, mackerel)—pull-tab preferred
• Instant oatmeal packets
• Cup noodles (hot water only)

Main Meals (when conditions allow cooking)

• Freeze-dried meals (Mountain House, Backpacker's Pantry): expensive but excellent for passages
• Canned soups and stews
• Pasta with commercially prepared sauce
• Rice (pressure cooker significantly reduces cooking time at sea)
• Long-life vacuum-sealed fresh meals (available in marine supply stores)
• Eggs (last 2–3 weeks unrefrigerated if unwashed; wax coating extends this)

Fresh Provisions (use first week)

• Vegetables that last: cabbage, carrots, onions, potatoes, squash
• Fruit: apples, oranges, bananas (goes fast; offset timing by buying some green)
• Cheese (vacuum-sealed, hard varieties last weeks)

Comfort Foods

Morale is a real safety factor on long passages. Coffee, chocolate, cookies, and crew favorites are worth the weight.

Safety and Medical

For the purposes of offshore provisioning, the medical kit is as critical as the food.

Seasickness medication: Have multiple options. Scopolamine patches (Transderm Scop) are the most effective but require prescription. Promethazine suppositories are the field gold standard because they work when the patient can't keep pills down. OTC: meclizine (Bonine) is less sedating than dimenhydrinate.

Dental emergencies: Dental Medic or Recapit for emergency tooth repair. Dental emergencies are more common on extended passages than many sailors realize.

Core offshore medical kit (separate article, but minimum):

• Antibiotics: amoxicillin-clavulanate and ciprofloxacin
• Pain management: ibuprofen, acetaminophen, and stronger if prescribed
• Wound care: comprehensive
• Suture kit or stapler (and the training to use it)
• Epipen if any crew has known anaphylaxis risk

Tools and Spare Parts

Provisions aren't just food. A passage that starts with a broken autopilot or a fouled watermaker changes everything.

Minimum passage spares:

• Impeller for every water pump
• Engine belts (all of them, in the right sizes)
• Engine zincs
• Fuel filters (quantity equal to your estimated engine hours)
• Watermaker membrane and service kit
• Fuses and circuit breakers matching your panel
• Epoxy putty (below-waterline emergency repair)
• Sheets and halyards (one spare set)
• Sail repair kit (tape, thread, needles, patches matching your sail material)

HAVEN Sailing Mode for Offshore Passages

HAVEN's Sailing mode includes offshore scenario guidance and marine safety protocols. Before departure, download your entire ocean region and coastal areas. On passage, the offline AI can help you:

• "My crew member has been vomiting for 12 hours and can't keep water down. What's the protocol?"
• "We have a water pump failure and our watermaker is down. How do we calculate our water reserve?"
• "I can hear a crackling sound in my crew member's breathing at rest. What are the HAPE warning signs?"
• "What's the decision framework for turning back vs. heaving to vs. continuing in building conditions?"

Provision well. Download everything before you leave the dock. The ocean doesn't have a resupply.