diff --git a/protocol/x/affiliates/keeper/grpc_query_test.go b/protocol/x/affiliates/keeper/grpc_query_test.go
index c29f8fb7d3..8c4ea7618b 100644
--- a/protocol/x/affiliates/keeper/grpc_query_test.go
+++ b/protocol/x/affiliates/keeper/grpc_query_test.go
@@ -99,7 +99,8 @@ func TestAffiliateInfo(t *testing.T) {
 
 			// Set up affiliate tiers
 			tiers := types.DefaultAffiliateTiers
-			k.UpdateAffiliateTiers(ctx, tiers)
+			err := k.UpdateAffiliateTiers(ctx, tiers)
+			require.NoError(t, err)
 
 			// Run the setup function
 			tc.setup(ctx, k, tApp)
@@ -174,7 +175,8 @@ func TestAllAffiliateTiers(t *testing.T) {
 	req := &types.AllAffiliateTiersRequest{}
 
 	tiers := types.DefaultAffiliateTiers
-	k.UpdateAffiliateTiers(ctx, tiers)
+	err := k.UpdateAffiliateTiers(ctx, tiers)
+	require.NoError(t, err)
 
 	res, err := k.AllAffiliateTiers(ctx, req)
 
diff --git a/protocol/x/affiliates/keeper/keeper.go b/protocol/x/affiliates/keeper/keeper.go
index 4aed7cbe84..20003b548f 100644
--- a/protocol/x/affiliates/keeper/keeper.go
+++ b/protocol/x/affiliates/keeper/keeper.go
@@ -220,11 +220,20 @@ func (k Keeper) GetTierForAffiliate(
 
 // UpdateAffiliateTiers updates the affiliate tiers.
 // Used primarily through governance.
-func (k Keeper) UpdateAffiliateTiers(ctx sdk.Context, affiliateTiers types.AffiliateTiers) {
+func (k Keeper) UpdateAffiliateTiers(ctx sdk.Context, affiliateTiers types.AffiliateTiers) error {
 	store := ctx.KVStore(k.storeKey)
-	// TODO(OTE-779): Check strictly increasing volume and
-	// staking requirements hold in UpdateAffiliateTiers
-	store.Set([]byte(types.AffiliateTiersKey), k.cdc.MustMarshal(&affiliateTiers))
+	affiliateTiersBytes := k.cdc.MustMarshal(&affiliateTiers)
+	tiers := affiliateTiers.GetTiers()
+	// start at 1, since 0 is the default tier.
+	for i := 1; i < len(tiers); i++ {
+		if tiers[i].ReqReferredVolumeQuoteQuantums <= tiers[i-1].ReqReferredVolumeQuoteQuantums ||
+			tiers[i].ReqStakedWholeCoins <= tiers[i-1].ReqStakedWholeCoins {
+			return errorsmod.Wrapf(types.ErrInvalidAffiliateTiers,
+				"tiers values must be strictly increasing")
+		}
+	}
+	store.Set([]byte(types.AffiliateTiersKey), affiliateTiersBytes)
+	return nil
 }
 
 func (k *Keeper) SetRevShareKeeper(revShareKeeper types.RevShareKeeper) {
diff --git a/protocol/x/affiliates/keeper/keeper_test.go b/protocol/x/affiliates/keeper/keeper_test.go
index 421f62cf55..61d792982a 100644
--- a/protocol/x/affiliates/keeper/keeper_test.go
+++ b/protocol/x/affiliates/keeper/keeper_test.go
@@ -145,10 +145,11 @@ func TestGetTakerFeeShareViaReferredVolume(t *testing.T) {
 	k := tApp.App.AffiliatesKeeper
 	// Set up affiliate tiers
 	affiliateTiers := types.DefaultAffiliateTiers
-	k.UpdateAffiliateTiers(ctx, affiliateTiers)
+	err := k.UpdateAffiliateTiers(ctx, affiliateTiers)
+	require.NoError(t, err)
 	stakingKeeper := tApp.App.StakingKeeper
 
-	err := stakingKeeper.SetDelegation(ctx,
+	err = stakingKeeper.SetDelegation(ctx,
 		stakingtypes.NewDelegation(constants.AliceAccAddress.String(),
 			constants.AliceValAddress.String(), math.LegacyNewDecFromBigInt(
 				new(big.Int).Mul(
@@ -194,13 +195,14 @@ func TestGetTakerFeeShareViaStakedAmount(t *testing.T) {
 	ctx = ctx.WithBlockTime(time.Now())
 	// Set up affiliate tiers
 	affiliateTiers := types.DefaultAffiliateTiers
-	k.UpdateAffiliateTiers(ctx, affiliateTiers)
+	err := k.UpdateAffiliateTiers(ctx, affiliateTiers)
+	require.NoError(t, err)
 
 	// Register affiliate and referee
 	affiliate := constants.AliceAccAddress.String()
 	referee := constants.BobAccAddress.String()
 	stakingKeeper := tApp.App.StakingKeeper
-	err := stakingKeeper.SetDelegation(ctx,
+	err = stakingKeeper.SetDelegation(ctx,
 		stakingtypes.NewDelegation(constants.AliceAccAddress.String(),
 			constants.AliceValAddress.String(), math.LegacyNewDecFromBigInt(
 				new(big.Int).Mul(
@@ -248,12 +250,13 @@ func TestGetTierForAffiliate_VolumeAndStake(t *testing.T) {
 	k := tApp.App.AffiliatesKeeper
 
 	affiliateTiers := types.DefaultAffiliateTiers
-	k.UpdateAffiliateTiers(ctx, affiliateTiers)
+	err := k.UpdateAffiliateTiers(ctx, affiliateTiers)
+	require.NoError(t, err)
 	affiliate := constants.AliceAccAddress.String()
 	referee := constants.BobAccAddress.String()
 	stakingKeeper := tApp.App.StakingKeeper
 
-	err := stakingKeeper.SetDelegation(ctx,
+	err = stakingKeeper.SetDelegation(ctx,
 		stakingtypes.NewDelegation(constants.AliceAccAddress.String(),
 			constants.AliceValAddress.String(), math.LegacyNewDecFromBigInt(
 				new(big.Int).Mul(
@@ -296,12 +299,52 @@ func TestUpdateAffiliateTiers(t *testing.T) {
 	ctx := tApp.InitChain()
 	k := tApp.App.AffiliatesKeeper
 
-	// Set up valid affiliate tiers
-	validTiers := types.DefaultAffiliateTiers
-	k.UpdateAffiliateTiers(ctx, validTiers)
+	tests := []struct {
+		name           string
+		affiliateTiers types.AffiliateTiers
+		expectedError  error
+	}{
+		{
+			name:           "Valid tiers",
+			affiliateTiers: types.DefaultAffiliateTiers,
+			expectedError:  nil,
+		},
+		{
+			name: "Invalid tiers - decreasing volume requirement",
+			affiliateTiers: types.AffiliateTiers{
+				Tiers: []types.AffiliateTiers_Tier{
+					{ReqReferredVolumeQuoteQuantums: 1000, ReqStakedWholeCoins: 100, TakerFeeSharePpm: 100},
+					{ReqReferredVolumeQuoteQuantums: 500, ReqStakedWholeCoins: 200, TakerFeeSharePpm: 200},
+				},
+			},
+			expectedError: types.ErrInvalidAffiliateTiers,
+		},
+		{
+			name: "Invalid tiers - decreasing staking requirement",
+			affiliateTiers: types.AffiliateTiers{
+				Tiers: []types.AffiliateTiers_Tier{
+					{ReqReferredVolumeQuoteQuantums: 1000, ReqStakedWholeCoins: 200, TakerFeeSharePpm: 100},
+					{ReqReferredVolumeQuoteQuantums: 2000, ReqStakedWholeCoins: 100, TakerFeeSharePpm: 200},
+				},
+			},
+			expectedError: types.ErrInvalidAffiliateTiers,
+		},
+	}
 
-	// Retrieve and validate updated tiers
-	updatedTiers, err := k.GetAllAffiliateTiers(ctx)
-	require.NoError(t, err)
-	require.Equal(t, validTiers, updatedTiers)
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			err := k.UpdateAffiliateTiers(ctx, tc.affiliateTiers)
+
+			if tc.expectedError != nil {
+				require.ErrorIs(t, err, tc.expectedError)
+			} else {
+				require.NoError(t, err)
+
+				// Retrieve and validate updated tiers
+				updatedTiers, err := k.GetAllAffiliateTiers(ctx)
+				require.NoError(t, err)
+				require.Equal(t, tc.affiliateTiers, updatedTiers)
+			}
+		})
+	}
 }
diff --git a/protocol/x/affiliates/keeper/msg_server.go b/protocol/x/affiliates/keeper/msg_server.go
index b21094d20b..6a308ca37e 100644
--- a/protocol/x/affiliates/keeper/msg_server.go
+++ b/protocol/x/affiliates/keeper/msg_server.go
@@ -51,7 +51,10 @@ func (k msgServer) UpdateAffiliateTiers(ctx context.Context,
 		)
 	}
 
-	k.Keeper.UpdateAffiliateTiers(sdkCtx, msg.Tiers)
+	err = k.Keeper.UpdateAffiliateTiers(sdkCtx, msg.Tiers)
+	if err != nil {
+		return nil, err
+	}
 
 	return &types.MsgUpdateAffiliateTiersResponse{}, nil
 }