diff --git a/SeaHaven.DataServices/Helpers/WorkOrderBoardDispatchAssignment.cs b/SeaHaven.DataServices/Helpers/WorkOrderBoardDispatchAssignment.cs
new file mode 100644
index 0000000..b257b66
--- /dev/null
+++ b/SeaHaven.DataServices/Helpers/WorkOrderBoardDispatchAssignment.cs
@@ -0,0 +1,28 @@
+namespace SeaHaven.DataServices.Helpers
+{
+    /// <summary>
+    /// SH-183: a cancelled or refused primary dispatch is not a live vendor assignment.
+    /// Verified/Completed remain live — the company that did the work.
+    /// </summary>
+    public static class WorkOrderBoardDispatchAssignment
+    {
+        public static bool IsInactivePrimaryDispatch(string? status)
+        {
+            var normalized = (status ?? string.Empty).Trim().ToLowerInvariant();
+            return normalized is "cancelled" or "canceled" or "refused";
+        }
+
+        public static (int? VendorId, string? VendorName) LiveVendor(
+            int? vendorId,
+            string? vendorName,
+            string? primaryDispatchStatus)
+        {
+            if (IsInactivePrimaryDispatch(primaryDispatchStatus))
+            {
+                return (null, null);
+            }
+
+            return (vendorId, vendorName);
+        }
+    }
+}
diff --git a/SeaHaven.DataServices/Helpers/WorkOrderBoardProjection.cs b/SeaHaven.DataServices/Helpers/WorkOrderBoardProjection.cs
index 04feeca..480d534 100644
--- a/SeaHaven.DataServices/Helpers/WorkOrderBoardProjection.cs
+++ b/SeaHaven.DataServices/Helpers/WorkOrderBoardProjection.cs
@@ -50,6 +50,7 @@ namespace SeaHaven.DataServices.Helpers
                     w.ScheduledEnd,
                     w.TargetWeek,
                     w.ScheduleWeekOnly,
+                    PrimaryDispatchStatus = w.PrimaryDispatch != null ? w.PrimaryDispatch.Status : null,
                     VendorId = w.PrimaryDispatch != null ? (int?)w.PrimaryDispatch.VendorId : null,
                     VendorName = w.PrimaryDispatch != null && w.PrimaryDispatch.Vendor != null
                         ? w.PrimaryDispatch.Vendor.CompanyName
@@ -124,6 +125,10 @@ namespace SeaHaven.DataServices.Helpers
                 var techPhone = !string.IsNullOrWhiteSpace(w.DispatchTechPhone)
                     ? w.DispatchTechPhone
                     : (!string.IsNullOrWhiteSpace(w.WoTechPhone) ? w.WoTechPhone : w.VendorPhone);
+                var (vendorId, vendorName) = WorkOrderBoardDispatchAssignment.LiveVendor(
+                    w.VendorId,
+                    w.VendorName,
+                    w.PrimaryDispatchStatus);
 
                 return new WorkOrderBoardRawRow(
                     w.Id,
@@ -150,8 +155,8 @@ namespace SeaHaven.DataServices.Helpers
                     w.ScheduledEnd,
                     w.TargetWeek,
                     w.ScheduleWeekOnly,
-                    w.VendorId,
-                    w.VendorName,
+                    vendorId,
+                    vendorName,
                     w.TechName,
                     techPhone,
                     w.DispatchApptDate,
@@ -170,6 +175,7 @@ namespace SeaHaven.DataServices.Helpers
                     w.HasUplift,
                     w.PrimaryUpliftStatus,
                     w.PrimaryUpliftAmount,
+                    w.PrimaryDispatchStatus,
                     isUnscheduled);
             }).ToList();
         }
diff --git a/SeaHaven.DataServices/Interfaces/WorkOrderBoardModels.cs b/SeaHaven.DataServices/Interfaces/WorkOrderBoardModels.cs
index f122889..6ae2928 100644
--- a/SeaHaven.DataServices/Interfaces/WorkOrderBoardModels.cs
+++ b/SeaHaven.DataServices/Interfaces/WorkOrderBoardModels.cs
@@ -58,6 +58,7 @@ namespace SeaHaven.DataServices.Interfaces
         bool HasUplift,
         string? PrimaryUpliftStatus,
         decimal? PrimaryUpliftAmount,
+        string? PrimaryDispatchStatus,
         bool IsUnscheduled);
 
     public record WorkOrderBoardQueryResult(
diff --git a/SeaHaven.Services/DTOs/WorkOrderBoardDTOs.cs b/SeaHaven.Services/DTOs/WorkOrderBoardDTOs.cs
index e59464c..865ef7a 100644
--- a/SeaHaven.Services/DTOs/WorkOrderBoardDTOs.cs
+++ b/SeaHaven.Services/DTOs/WorkOrderBoardDTOs.cs
@@ -58,6 +58,10 @@ namespace SeaHaven.Services.DTOs
         public string? DayGroup { get; set; }
         public int? VendorId { get; set; }
         public string? VendorName { get; set; }
+        /// <summary>
+        /// Primary dispatch status (SH-183). Inactive statuses are not a live company assignment.
+        /// </summary>
+        public string? PrimaryDispatchStatus { get; set; }
         public string? TechName { get; set; }
         public string? TechPhone { get; set; }
         public DateTime? ApptDate { get; set; }
diff --git a/SeaHaven.Services/Implementation/WorkOrderBoardService.cs b/SeaHaven.Services/Implementation/WorkOrderBoardService.cs
index 4aa70ad..c1b2f42 100644
--- a/SeaHaven.Services/Implementation/WorkOrderBoardService.cs
+++ b/SeaHaven.Services/Implementation/WorkOrderBoardService.cs
@@ -1,5 +1,6 @@
 using System.Security.Claims;
 using Data.SeaHavenIndustries.Enums;
+using SeaHaven.DataServices.Helpers;
 using SeaHaven.DataServices.Interfaces;
 using SeaHaven.Services.DTOs;
 using SeaHaven.Services.Helpers;
@@ -86,6 +87,10 @@ namespace SeaHaven.Services.Implementation
             // Time prefers WO ScheduledStart/End (dispatcher window), then dispatch datetime.
             var apptStart = row.ScheduledStart ?? row.DispatchApptDate;
             var apptEnd = row.ScheduledEnd;
+            var (vendorId, vendorName) = WorkOrderBoardDispatchAssignment.LiveVendor(
+                row.VendorId,
+                row.VendorName,
+                row.PrimaryDispatchStatus);
 
             return new WorkOrderBoardRowDto
             {
@@ -113,8 +118,9 @@ namespace SeaHaven.Services.Implementation
                 TargetWeek = row.TargetWeek,
                 ScheduleWeekOnly = row.ScheduleWeekOnly,
                 DayGroup = WorkOrderDerivedFields.GetDayGroup(row.ScheduledDate),
-                VendorId = row.VendorId,
-                VendorName = row.VendorName,
+                VendorId = vendorId,
+                VendorName = vendorName,
+                PrimaryDispatchStatus = row.PrimaryDispatchStatus,
                 TechName = row.TechName,
                 TechPhone = row.TechPhone,
                 ApptDate = row.DispatchApptDate ?? row.ScheduledDate,
diff --git a/SeaHavenIndustries.Tests/WorkOrderBoardDispatchAssignmentTests.cs b/SeaHavenIndustries.Tests/WorkOrderBoardDispatchAssignmentTests.cs
new file mode 100644
index 0000000..a49e275
--- /dev/null
+++ b/SeaHavenIndustries.Tests/WorkOrderBoardDispatchAssignmentTests.cs
@@ -0,0 +1,35 @@
+using SeaHaven.DataServices.Helpers;
+
+namespace SeaHavenIndustries.Tests;
+
+public class WorkOrderBoardDispatchAssignmentTests
+{
+    [Theory]
+    [InlineData("Cancelled")]
+    [InlineData("Canceled")]
+    [InlineData("Refused")]
+    [InlineData(" cancelled ")]
+    [InlineData("CANCELED")]
+    [InlineData("refused")]
+    public void LiveVendor_InactiveStatus_ClearsAssignment(string status)
+    {
+        var (vendorId, vendorName) = WorkOrderBoardDispatchAssignment.LiveVendor(45, "Acme HVAC", status);
+        Assert.Null(vendorId);
+        Assert.Null(vendorName);
+        Assert.True(WorkOrderBoardDispatchAssignment.IsInactivePrimaryDispatch(status));
+    }
+
+    [Theory]
+    [InlineData(null)]
+    [InlineData("")]
+    [InlineData("Sent")]
+    [InlineData("Verified")]
+    [InlineData("Completed")]
+    public void LiveVendor_LiveOrMissingStatus_KeepsVendorIdWhenNameEmpty(string? status)
+    {
+        var (vendorId, vendorName) = WorkOrderBoardDispatchAssignment.LiveVendor(45, null, status);
+        Assert.Equal(45, vendorId);
+        Assert.Null(vendorName);
+        Assert.False(WorkOrderBoardDispatchAssignment.IsInactivePrimaryDispatch(status));
+    }
+}
diff --git a/SeaHavenIndustries.Tests/WorkOrderBoardInactiveVendorTests.cs b/SeaHavenIndustries.Tests/WorkOrderBoardInactiveVendorTests.cs
new file mode 100644
index 0000000..d2adc8e
--- /dev/null
+++ b/SeaHavenIndustries.Tests/WorkOrderBoardInactiveVendorTests.cs
@@ -0,0 +1,102 @@
+using Data.SeaHavenIndustries;
+using Data.SeaHavenIndustries.Enums;
+using Microsoft.EntityFrameworkCore;
+using SeaHaven.DataServices.Implementation;
+using SeaHaven.DataServices.Interfaces;
+using SeaHaven.Services.Implementation;
+
+namespace SeaHavenIndustries.Tests;
+
+public class WorkOrderBoardInactiveVendorTests
+{
+    private static ApplicationDbContext CreateContext()
+    {
+        var options = new DbContextOptionsBuilder<ApplicationDbContext>()
+            .UseInMemoryDatabase(Guid.NewGuid().ToString())
+            .Options;
+        return new ApplicationDbContext(options);
+    }
+
+    private static async Task SeedPrimaryDispatchAsync(
+        ApplicationDbContext context,
+        string? dispatchStatus,
+        string? companyName)
+    {
+        context.Vendors.Add(new Vendor { Id = 1, CompanyName = companyName });
+        context.Dispatches.Add(new Dispatch
+        {
+            Id = 10,
+            VendorId = 1,
+            WorkOrderId = 1,
+            Status = dispatchStatus,
+            ScheduledDate = new DateTime(2026, 6, 24, 8, 0, 0)
+        });
+        context.workOrders.Add(new WorkOrder
+        {
+            Id = 1,
+            InternalWONumber = "10000000001",
+            ScheduledDate = new DateTime(2026, 6, 23),
+            LifecycleStatus = LifecycleStatus.Scheduled,
+            PrimaryDispatchId = 10,
+            SiteCode = "BK5"
+        });
+        await context.SaveChangesAsync();
+    }
+
+    [Theory]
+    [InlineData("Cancelled")]
+    [InlineData("Canceled")]
+    [InlineData("Refused")]
+    public async Task GetBoardRows_InactivePrimaryDispatch_OmitsVendorAssignment(string status)
+    {
+        await using var context = CreateContext();
+        await SeedPrimaryDispatchAsync(context, status, "Acme HVAC");
+        var weekStart = new DateOnly(2026, 6, 22);
+
+        var result = await new WorkOrderBoardDataService(context).GetBoardRowsAsync(new WorkOrderBoardQuery(
+            weekStart,
+            weekStart.AddDays(4),
+            null,
+            false,
+            null,
+            false,
+            null,
+            null));
+
+        var raw = Assert.Single(result.ScheduledRows);
+        Assert.Null(raw.VendorId);
+        Assert.Null(raw.VendorName);
+        Assert.Equal(status, raw.PrimaryDispatchStatus);
+
+        var dto = WorkOrderBoardService.MapRawRow(raw, DateTime.UtcNow);
+        Assert.Null(dto.VendorId);
+        Assert.Null(dto.VendorName);
+        Assert.Equal(status, dto.PrimaryDispatchStatus);
+    }
+
+    [Fact]
+    public async Task GetBoardRows_LiveDispatchWithEmptyCompanyName_KeepsVendorId()
+    {
+        await using var context = CreateContext();
+        await SeedPrimaryDispatchAsync(context, "Sent", "");
+        var weekStart = new DateOnly(2026, 6, 22);
+
+        var result = await new WorkOrderBoardDataService(context).GetBoardRowsAsync(new WorkOrderBoardQuery(
+            weekStart,
+            weekStart.AddDays(4),
+            null,
+            false,
+            null,
+            false,
+            null,
+            null));
+
+        var raw = Assert.Single(result.ScheduledRows);
+        Assert.Equal(1, raw.VendorId);
+        Assert.Equal("Sent", raw.PrimaryDispatchStatus);
+
+        var dto = WorkOrderBoardService.MapRawRow(raw, DateTime.UtcNow);
+        Assert.Equal(1, dto.VendorId);
+        Assert.Equal("Sent", dto.PrimaryDispatchStatus);
+    }
+}