diff --git a/backend/src/services/dto/service.dto.ts b/backend/src/services/dto/service.dto.ts
index 7e3bc55..bd135bf 100644
--- a/backend/src/services/dto/service.dto.ts
+++ b/backend/src/services/dto/service.dto.ts
@@ -64,3 +64,11 @@ export class UpdateServiceStatusDto {
   @IsEnum(ServiceStatus)
   status: ServiceStatus;
 }
+
+export class BlockSlotDto {
+  @IsDateString()
+  day: string;
+
+  @Matches(/^\d{2}:\d{2}$/)
+  range1_hour1: string;
+}
diff --git a/backend/src/services/services.controller.ts b/backend/src/services/services.controller.ts
index e8cbf46..2afdf8b 100644
--- a/backend/src/services/services.controller.ts
+++ b/backend/src/services/services.controller.ts
@@ -2,7 +2,7 @@ import { Controller, Get, Post, Patch, Param, Body, UseGuards, Req, Query } from
 import { ApiTags, ApiBearerAuth, ApiQuery } from '@nestjs/swagger';
 import { ServicesService } from './services.service';
 import { JwtAuthGuard } from '../auth/jwt-auth.guard';
-import { CreateServiceDto, UpdateServiceStatusDto } from './dto/service.dto';
+import { CreateServiceDto, UpdateServiceStatusDto, BlockSlotDto } from './dto/service.dto';
 
 @ApiTags('Services')
 @Controller('services')
@@ -16,6 +16,13 @@ export class ServicesController {
     return this.services.create({ ...dto, user_id: req.user.sub });
   }
 
+  @Post('block')
+  @UseGuards(JwtAuthGuard)
+  @ApiBearerAuth()
+  blockSlot(@Req() req, @Body() dto: BlockSlotDto) {
+    return this.services.blockSlot(req.user.sub, dto);
+  }
+
   @Get()
   @UseGuards(JwtAuthGuard)
   @ApiBearerAuth()
diff --git a/backend/src/services/services.service.ts b/backend/src/services/services.service.ts
index f96bf11..ed06c67 100644
--- a/backend/src/services/services.service.ts
+++ b/backend/src/services/services.service.ts
@@ -150,6 +150,32 @@ export class ServicesService {
     return updated;
   }
 
+  async blockSlot(userId: string, data: { day: string; range1_hour1: string }) {
+    const prof = await this.prisma.professionals.findUnique({ where: { user_id: userId } });
+    if (!prof) throw new NotFoundException('No eres un profesional');
+
+    const slotTime = new Date(`1970-01-01T${data.range1_hour1}:00`);
+    const conflict = await this.prisma.services.findFirst({
+      where: {
+        professional_id: prof.id,
+        day: new Date(data.day),
+        range1_hour1: slotTime,
+        status: { notIn: ['denied', 'cancelled'] },
+      },
+    });
+    if (conflict) throw new BadRequestException('Este horario ya está ocupado o bloqueado');
+
+    return this.prisma.services.create({
+      data: {
+        professional_id: prof.id,
+        user_id: prof.user_id,
+        day: new Date(data.day),
+        range1_hour1: slotTime,
+        status: 'self_booked' as any,
+      },
+    });
+  }
+
   async findByUser(userId: string, page = 1, limit = 20) {
     const skip = (page - 1) * limit;
     const where = { user_id: userId, status: { notIn: ['completed' as const, 'cancelled' as const, 'denied' as const] } };