Bidding a suit after opposition have opened
An overcall is a bid you make when the opposition have already opened the bidding. There are a few reasons why you might want to overcall. The most obvious, of course, is that you get to play the hand. It can also help if you end up defending the hand because it'll tell partner what to lead. And an overcall can also be a disruptive bid. Even a simple overcall can take away bidding space from the opposition and make it harder for them to get to their best contract. Finally, of course, it's fun to bid!
Suit quality is important when overcalling. On the following hand East has opened 1♥ and I'm going to bid 1♠. So my 1♠ is an overcall.
The most important thing to consider when you're overcalling is the quality of your suit. Here I've got a good 5-card suit. And that's the type of hand that you really want to be overcalling on.
Let's have a look at a few more examples.
East has opened 1♥ and I have a 5-card spade suit 10 points.
I've only got one honour and it's not such a great hand, so I'd rather pass.
East opens 1♥ and this time, I'm going to overcall 2♦.
I have to go to the two level but I've got a really nice diamond suit, so that makes it worthwhile. Even if I don't get to play the hand my partner will know to lead a diamond, which I'll be very happy about.
Responding to an overall
Overcalls are not opening bids so responding to an overcall is not the same as responding to an opening bid.
Change of suit
Your first job is to discuss with partner if a change of suit should be forcing or not. There's no right or wrong, some players say a change of suit is forcing others say it's not. There are pros and cons to both approaches. Just make sure you have the conversation!
A 1NT overcall shows 15-18 points. Most players use the same subsequent bidding methods as they would over a 1NT opening.
If the opposition open at the 2 level then 2NT also shows a strong balanced hand. Stayman and transfers can still be used.
If the opposition open at the 3 level then 3NT also shows a strong balanced hand. Stayman isn't normally used now. Instead transfers can be used for every suit. A transfer to the opener's suit is either takeout or a slam invitation.
Jump overcalls are almost always 6 card suits. Some players use jump overcalls to show weak hands, the same sort of thing as a weak 2 opening bid. Another common approach is to play intermediate jumps which typically show around 12-16 points.
The Unusual 2NT is a jump overcall of 2NT showing 5-5 in the lower 2 unbid suits
East has opened 1♠ and we have to decide what to do in the overcall position.
We could bid 2♣ but the hands are a little bit strong for that. An overcall normally shows a maximum of about 15, 16, maybe 17 points and we have 17, but really great shape. So I'm not so keen on that. And if I bid 2♣, it's going to be hard to show that diamond suit later. I could bid two 2♦, but that seems no better, because I've got all those clubs.
Double is an option, but I've only got those two hearts. And if I double partner always bids my short suit so partner bids hearts and that's not so good either.
This is a good hand to use what's called the Unusual 2NT overcall. It's unusual because if I had a strong hand, I would double. 1NT Trump would be a strong, balanced hand. So what's 2NT? That would be unusual. The unusual 2NT! And a jump to 2NT as an overcall shows two five cards suits, and it's the lower two unbid suits. So in this case, that's clubs and diamonds. So I can 2NT here. I've shown at least five clubs and five diamonds. And I don't care, which one partner bids.
Michaels Cue Bid
A Michaels Cue Bid is a way of showing 2 suits at the same time when overcalling.
Your suits should be good to make a Michaels Cue Bid. A useful rule of thumb is that each suit should contain two of the top four honors. You don't have to have an opening hand - just good suits, so the strength may vary. The reason that you need to have good suits is that the auction may easily be forced to the 3-level.
This is a perfect Michaels Cue Bid. Partner now has an accurate picture of your hand and can support either of your suit, secure in the knowledge that your suits are of good quality.
2♥ shows the other major plus at least 5 of a minor.
Responding to a Michaels Cue Bid
If you have a trump fit
In general you should respond as you would to a normal overcall, except that you are spoilt for choice! Support partner with a fit in one or both of the suits. Bid game if you are strong and have a fit. Even if you do not have many high card points, the more trumps you have the higher you should bid.
Partner has shown hearts and spades. You have support for both suits and a good hand. Bid 4♠. You are now not bidding just on your trump fit but on your strength. Your club weakness is not a worry as partner is likely to have two at the most.
You want to find partner's other suit
Partner has shown 5 hearts and 5 of a minor. You don't want to play in hearts but rather in partner's minor. You are not interested in game so bid 3♣. Partner will pass with clubs or else convert to 3♦.
Leaping Michaels is used over a weak 2 level opening or a Multi 2♦. It shows two 5 card suits.
(2♦ multi) - 3♠ = 5♠+5m - 4♣ = 5♥+5♣ - 4♦ = 5♥+5♦
Non Leaping Michaels
Non Leaping Michaels is used over a 3 level preempt to show two 5-card suits.
(3♣) - 4♣ = ♠+♥ - 4♦ = ♦+M (3♦) - 4♣ = ♣+M - 4♦ = ♠+♥ (3♥) - 4♣ = ♣+♠ - 4♦ = ♦+♠ (3♠) - 4♣ = ♣+♥ - 4♦ = ♦+♥