diff --git a/services/trade_builder.py b/services/trade_builder.py
index 879959f..8ab1d5d 100644
--- a/services/trade_builder.py
+++ b/services/trade_builder.py
@@ -3,6 +3,7 @@ Trade Builder Service
 
 Extends the TransactionBuilder to support multi-team trades and player exchanges.
 """
+
 import logging
 from typing import Dict, List, Optional, Set
 from datetime import datetime, timezone
@@ -12,10 +13,14 @@ from config import get_config
 from models.trade import Trade, TradeMove, TradeStatus
 from models.team import Team, RosterType
 from models.player import Player
-from services.transaction_builder import TransactionBuilder, RosterValidationResult, TransactionMove
+from services.transaction_builder import (
+    TransactionBuilder,
+    RosterValidationResult,
+    TransactionMove,
+)
 from services.team_service import team_service
 
-logger = logging.getLogger(f'{__name__}.TradeBuilder')
+logger = logging.getLogger(f"{__name__}.TradeBuilder")
 
 
 class TradeValidationResult:
@@ -52,7 +57,9 @@ class TradeValidationResult:
             suggestions.extend(validation.suggestions)
         return suggestions
 
-    def get_participant_validation(self, team_id: int) -> Optional[RosterValidationResult]:
+    def get_participant_validation(
+        self, team_id: int
+    ) -> Optional[RosterValidationResult]:
         """Get validation result for a specific team."""
         return self.participant_validations.get(team_id)
 
@@ -64,7 +71,12 @@ class TradeBuilder:
     Extends the functionality of TransactionBuilder to support trades between teams.
     """
 
-    def __init__(self, initiated_by: int, initiating_team: Team, season: int = get_config().sba_season):
+    def __init__(
+        self,
+        initiated_by: int,
+        initiating_team: Team,
+        season: int = get_config().sba_season,
+    ):
         """
         Initialize trade builder.
 
@@ -79,7 +91,7 @@ class TradeBuilder:
             status=TradeStatus.DRAFT,
             initiated_by=initiated_by,
             created_at=datetime.now(timezone.utc).isoformat(),
-            season=season
+            season=season,
         )
 
         # Add the initiating team as first participant
@@ -91,7 +103,9 @@ class TradeBuilder:
         # Track which teams have accepted the trade (team_id -> True)
         self.accepted_teams: Set[int] = set()
 
-        logger.info(f"TradeBuilder initialized: {self.trade.trade_id} by user {initiated_by} for {initiating_team.abbrev}")
+        logger.info(
+            f"TradeBuilder initialized: {self.trade.trade_id} by user {initiated_by} for {initiating_team.abbrev}"
+        )
 
     @property
     def trade_id(self) -> str:
@@ -127,7 +141,11 @@ class TradeBuilder:
     @property
     def pending_teams(self) -> List[Team]:
         """Get list of teams that haven't accepted yet."""
-        return [team for team in self.participating_teams if team.id not in self.accepted_teams]
+        return [
+            team
+            for team in self.participating_teams
+            if team.id not in self.accepted_teams
+        ]
 
     def accept_trade(self, team_id: int) -> bool:
         """
@@ -140,7 +158,9 @@ class TradeBuilder:
             True if all teams have now accepted, False otherwise
         """
         self.accepted_teams.add(team_id)
-        logger.info(f"Team {team_id} accepted trade {self.trade_id}. Accepted: {len(self.accepted_teams)}/{self.team_count}")
+        logger.info(
+            f"Team {team_id} accepted trade {self.trade_id}. Accepted: {len(self.accepted_teams)}/{self.team_count}"
+        )
         return self.all_teams_accepted
 
     def reject_trade(self) -> None:
@@ -160,7 +180,9 @@ class TradeBuilder:
         Returns:
             Dict mapping team_id to acceptance status (True/False)
         """
-        return {team.id: team.id in self.accepted_teams for team in self.participating_teams}
+        return {
+            team.id: team.id in self.accepted_teams for team in self.participating_teams
+        }
 
     def has_team_accepted(self, team_id: int) -> bool:
         """Check if a specific team has accepted."""
@@ -184,7 +206,9 @@ class TradeBuilder:
         participant = self.trade.add_participant(team)
 
         # Create transaction builder for this team
-        self._team_builders[team.id] = TransactionBuilder(team, self.trade.initiated_by, self.trade.season)
+        self._team_builders[team.id] = TransactionBuilder(
+            team, self.trade.initiated_by, self.trade.season
+        )
 
         # Register team in secondary index for multi-GM access
         trade_key = f"{self.trade.initiated_by}:trade"
@@ -209,7 +233,10 @@ class TradeBuilder:
 
         # Check if team has moves - prevent removal if they do
         if participant.all_moves:
-            return False, f"{participant.team.abbrev} has moves in this trade and cannot be removed"
+            return (
+                False,
+                f"{participant.team.abbrev} has moves in this trade and cannot be removed",
+            )
 
         # Remove team
         removed = self.trade.remove_participant(team_id)
@@ -229,7 +256,7 @@ class TradeBuilder:
         from_team: Team,
         to_team: Team,
         from_roster: RosterType,
-        to_roster: RosterType
+        to_roster: RosterType,
     ) -> tuple[bool, str]:
         """
         Add a player move to the trade.
@@ -246,7 +273,10 @@ class TradeBuilder:
         """
         # Validate player is not from Free Agency
         if player.team_id == get_config().free_agent_team_id:
-            return False, f"Cannot add {player.name} from Free Agency. Players must be traded from teams within the organizations involved in the trade."
+            return (
+                False,
+                f"Cannot add {player.name} from Free Agency. Players must be traded from teams within the organizations involved in the trade.",
+            )
 
         # Validate player has a valid team assignment
         if not player.team_id:
@@ -259,7 +289,10 @@ class TradeBuilder:
 
         # Check if player's team is in the same organization as from_team
         if not player_team.is_same_organization(from_team):
-            return False, f"{player.name} is on {player_team.abbrev}, they are not eligible to be added to the trade."
+            return (
+                False,
+                f"{player.name} is on {player_team.abbrev}, they are not eligible to be added to the trade.",
+            )
 
         # Ensure both teams are participating (check by organization for ML authority)
         from_participant = self.trade.get_participant_by_organization(from_team)
@@ -274,7 +307,10 @@ class TradeBuilder:
         for participant in self.trade.participants:
             for existing_move in participant.all_moves:
                 if existing_move.player.id == player.id:
-                    return False, f"{player.name} is already involved in a move in this trade"
+                    return (
+                        False,
+                        f"{player.name} is already involved in a move in this trade",
+                    )
 
         # Create trade move
         trade_move = TradeMove(
@@ -284,7 +320,7 @@ class TradeBuilder:
             from_team=from_team,
             to_team=to_team,
             source_team=from_team,
-            destination_team=to_team
+            destination_team=to_team,
         )
 
         # Add to giving team's moves
@@ -303,7 +339,7 @@ class TradeBuilder:
             from_roster=from_roster,
             to_roster=RosterType.FREE_AGENCY,  # Conceptually leaving the org
             from_team=from_team,
-            to_team=None
+            to_team=None,
         )
 
         # Move for receiving team (player joining)
@@ -312,19 +348,23 @@ class TradeBuilder:
             from_roster=RosterType.FREE_AGENCY,  # Conceptually joining from outside
             to_roster=to_roster,
             from_team=None,
-            to_team=to_team
+            to_team=to_team,
         )
 
         # Add moves to respective builders
         # Skip pending transaction check for trades - they have their own validation workflow
-        from_success, from_error = await from_builder.add_move(from_move, check_pending_transactions=False)
+        from_success, from_error = await from_builder.add_move(
+            from_move, check_pending_transactions=False
+        )
         if not from_success:
             # Remove from trade if builder failed
             from_participant.moves_giving.remove(trade_move)
             to_participant.moves_receiving.remove(trade_move)
             return False, f"Error adding move to {from_team.abbrev}: {from_error}"
 
-        to_success, to_error = await to_builder.add_move(to_move, check_pending_transactions=False)
+        to_success, to_error = await to_builder.add_move(
+            to_move, check_pending_transactions=False
+        )
         if not to_success:
             # Rollback both if second failed
             from_builder.remove_move(player.id)
@@ -332,15 +372,13 @@ class TradeBuilder:
             to_participant.moves_receiving.remove(trade_move)
             return False, f"Error adding move to {to_team.abbrev}: {to_error}"
 
-        logger.info(f"Added player move to trade {self.trade_id}: {trade_move.description}")
+        logger.info(
+            f"Added player move to trade {self.trade_id}: {trade_move.description}"
+        )
         return True, ""
 
     async def add_supplementary_move(
-        self,
-        team: Team,
-        player: Player,
-        from_roster: RosterType,
-        to_roster: RosterType
+        self, team: Team, player: Player, from_roster: RosterType, to_roster: RosterType
     ) -> tuple[bool, str]:
         """
         Add a supplementary move (internal organizational move) for roster legality.
@@ -366,7 +404,7 @@ class TradeBuilder:
             from_team=team,
             to_team=team,
             source_team=team,
-            destination_team=team
+            destination_team=team,
         )
 
         # Add to participant's supplementary moves
@@ -379,16 +417,20 @@ class TradeBuilder:
             from_roster=from_roster,
             to_roster=to_roster,
             from_team=team,
-            to_team=team
+            to_team=team,
         )
 
         # Skip pending transaction check for trade supplementary moves
-        success, error = await builder.add_move(trans_move, check_pending_transactions=False)
+        success, error = await builder.add_move(
+            trans_move, check_pending_transactions=False
+        )
         if not success:
             participant.supplementary_moves.remove(supp_move)
             return False, error
 
-        logger.info(f"Added supplementary move for {team.abbrev}: {supp_move.description}")
+        logger.info(
+            f"Added supplementary move for {team.abbrev}: {supp_move.description}"
+        )
         return True, ""
 
     async def remove_move(self, player_id: int) -> tuple[bool, str]:
@@ -432,21 +474,41 @@ class TradeBuilder:
         for builder in self._team_builders.values():
             builder.remove_move(player_id)
 
-        logger.info(f"Removed move from trade {self.trade_id}: {removed_move.description}")
+        logger.info(
+            f"Removed move from trade {self.trade_id}: {removed_move.description}"
+        )
         return True, ""
 
-    async def validate_trade(self, next_week: Optional[int] = None) -> TradeValidationResult:
+    async def validate_trade(
+        self, next_week: Optional[int] = None
+    ) -> TradeValidationResult:
         """
         Validate the entire trade including all teams' roster legality.
 
+        Validates against next week's projected roster (current roster + pending
+        transactions), matching the behavior of /dropadd validation.
+
         Args:
-            next_week: Week to validate for (optional)
+            next_week: Week to validate for (auto-fetched if not provided)
 
         Returns:
             TradeValidationResult with comprehensive validation
         """
         result = TradeValidationResult()
 
+        # Auto-fetch next week so validation includes pending transactions
+        if next_week is None:
+            try:
+                from services.league_service import league_service
+
+                current_state = await league_service.get_current_state()
+                next_week = (current_state.week + 1) if current_state else 1
+            except Exception as e:
+                logger.warning(
+                    f"Could not determine next week for trade validation: {e}"
+                )
+                next_week = None
+
         # Validate trade structure
         is_balanced, balance_errors = self.trade.validate_trade_balance()
         if not is_balanced:
@@ -472,13 +534,17 @@ class TradeBuilder:
         if self.team_count < 2:
             result.trade_suggestions.append("Add another team to create a trade")
 
-        logger.debug(f"Trade validation for {self.trade_id}: Legal={result.is_legal}, Errors={len(result.all_errors)}")
+        logger.debug(
+            f"Trade validation for {self.trade_id}: Legal={result.is_legal}, Errors={len(result.all_errors)}"
+        )
         return result
 
     def _get_or_create_builder(self, team: Team) -> TransactionBuilder:
         """Get or create a transaction builder for a team."""
         if team.id not in self._team_builders:
-            self._team_builders[team.id] = TransactionBuilder(team, self.trade.initiated_by, self.trade.season)
+            self._team_builders[team.id] = TransactionBuilder(
+                team, self.trade.initiated_by, self.trade.season
+            )
         return self._team_builders[team.id]
 
     def clear_trade(self) -> None:
@@ -592,4 +658,4 @@ def clear_trade_builder_by_team(team_id: int) -> bool:
 
 def get_active_trades() -> Dict[str, TradeBuilder]:
     """Get all active trade builders (for debugging/admin purposes)."""
-    return _active_trade_builders.copy()
\ No newline at end of file
+    return _active_trade_builders.copy()