I contributed more to our house deposit, do we still split it 50/50?

The difficulty with your question is that many factor actually affect the answer. I will therefore give a general overview of the rule and suggest you seek legal counsel for an answer suited to your exact situation.

The wording of your question indicated you are in a common-law relationship. Without an agreement, you are presumed 50/50 owner with your spouse. It would therefore be expected that you contribute to 50% of the expenses.

What must be remembered is that there is a distinction to be made between your right of ownership and the actual loan (guaranteed by mortgage). When you paid the down payment on the house, you technically paid off part of the loan for which, unless specified otherwise, you are 100% responsible for. There would then be no legal justification for claiming your down payment since the down payment had nothing to do with actual ownership of the house.

That said, there are legal mechanisms that would permit you to recuperate the down payment based on unjust enrichment. It must be noted however, that this remedy is not often available to common law relationships.