diff --git a/pkg/mycarehub/usecases/client/client.go b/pkg/mycarehub/usecases/client/client.go
index 0d3ccb98..a8292c24 100644
--- a/pkg/mycarehub/usecases/client/client.go
+++ b/pkg/mycarehub/usecases/client/client.go
@@ -2,6 +2,7 @@ package client
 
 import (
 	"context"
+	"fmt"
 
 	"github.com/savannahghi/mycarehub/pkg/mycarehub/application/dto"
 	"github.com/savannahghi/mycarehub/pkg/mycarehub/application/enums"
@@ -133,6 +134,15 @@ func (cl *UseCasesClientImpl) RegisterClient(
 	userInput *dto.UserInput,
 	clientInput *dto.ClientProfileInput,
 ) (*domain.ClientUserProfile, error) {
+
+	if userInput == nil {
+		return nil, fmt.Errorf("user input cannot be nil")
+	}
+
+	if clientInput == nil {
+		return nil, fmt.Errorf("client input cannot be nil")
+	}
+
 	return cl.Create.RegisterClient(ctx, userInput, clientInput)
 }
 
diff --git a/pkg/mycarehub/usecases/client/client_unit_test.go b/pkg/mycarehub/usecases/client/client_unit_test.go
new file mode 100644
index 00000000..59f5a73c
--- /dev/null
+++ b/pkg/mycarehub/usecases/client/client_unit_test.go
@@ -0,0 +1,126 @@
+package client
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"github.com/brianvoe/gofakeit"
+	"github.com/savannahghi/enumutils"
+	"github.com/savannahghi/feedlib"
+	"github.com/savannahghi/mycarehub/pkg/mycarehub/application/dto"
+	"github.com/savannahghi/mycarehub/pkg/mycarehub/application/enums"
+	"github.com/savannahghi/mycarehub/pkg/mycarehub/domain"
+	pgMock "github.com/savannahghi/mycarehub/pkg/mycarehub/infrastructure/database/postgres/mock"
+	"github.com/savannahghi/mycarehub/pkg/mycarehub/usecases/client/mock"
+)
+
+func TestUseCasesClientImpl_RegisterClient_Unittest(t *testing.T) {
+	ctx := context.Background()
+
+	addresses := &dto.AddressesInput{
+		Type:       enums.AddressesTypePostal,
+		Text:       gofakeit.BeerAlcohol(),
+		Country:    enums.CountryTypeKenya,
+		PostalCode: gofakeit.BeerName(),
+		County:     enums.CountyTypeNairobi,
+		Active:     true,
+	}
+
+	userInput := &dto.UserInput{
+		Username:    gofakeit.Username(),
+		DisplayName: gofakeit.BeerAlcohol(),
+		FirstName:   gofakeit.FirstName(),
+		MiddleName:  gofakeit.BeerAlcohol(),
+		LastName:    gofakeit.LastName(),
+		UserType:    enums.ClientUser,
+		Gender:      enumutils.GenderFemale,
+		Contacts:    []*dto.ContactInput{},
+		Languages:   []enumutils.Language{enumutils.LanguageSw},
+		Flavour:     feedlib.FlavourConsumer,
+		Address:     []*dto.AddressesInput{addresses},
+	}
+
+	clientInput := &dto.ClientProfileInput{
+		ClientType: enums.ClientTypeOvc,
+	}
+
+	type args struct {
+		ctx         context.Context
+		userInput   *dto.UserInput
+		clientInput *dto.ClientProfileInput
+	}
+	tests := []struct {
+		name    string
+		args    args
+		wantErr bool
+	}{
+		{
+			name: "Happy case",
+			args: args{
+				ctx:         ctx,
+				userInput:   userInput,
+				clientInput: clientInput,
+			},
+			wantErr: false,
+		},
+
+		{
+			name: "Sad case - nil user input",
+			args: args{
+				ctx:         ctx,
+				userInput:   nil,
+				clientInput: clientInput,
+			},
+			wantErr: true,
+		},
+
+		{
+			name: "Sad case - nil client input",
+			args: args{
+				ctx:         ctx,
+				userInput:   userInput,
+				clientInput: nil,
+			},
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+
+			fakeDB := pgMock.NewPostgresMock()
+			fakeClient := mock.NewClientUsecaseMock()
+
+			c := NewUseCasesClientImpl(fakeDB, fakeDB, fakeDB)
+
+			if tt.name == "Sad case - nil user input" {
+				fakeClient.MockRegisterClientFn = func(ctx context.Context, userInput *dto.UserInput, clientInput *dto.ClientProfileInput) (*domain.ClientUserProfile, error) {
+					return nil, fmt.Errorf("failed to register client")
+				}
+			}
+
+			if tt.name == "Sad case - nil client input" {
+				fakeClient.MockRegisterClientFn = func(ctx context.Context, userInput *dto.UserInput, clientInput *dto.ClientProfileInput) (*domain.ClientUserProfile, error) {
+					return nil, fmt.Errorf("failed to register client")
+				}
+			}
+
+			if tt.name == "Sad case - nil context" {
+				fakeClient.MockRegisterClientFn = func(ctx context.Context, userInput *dto.UserInput, clientInput *dto.ClientProfileInput) (*domain.ClientUserProfile, error) {
+					return nil, fmt.Errorf("failed to register client")
+				}
+			}
+
+			got, err := c.RegisterClient(tt.args.ctx, tt.args.userInput, tt.args.clientInput)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("UseCasesClientImpl.RegisterClient() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+
+			if !tt.wantErr && got == nil {
+				t.Errorf("expected client registration output not to be nil for %v", tt.name)
+				return
+			}
+		})
+	}
+}