Your own parish can be your first option for meaningful giving. Inquire whether your parish has an endowment or building fund for a contribution with a lasting impact.
You might also consider giving to one or more monasteries that have blessed you with prayer and hospitality. Contact the monastery to ensure that you name it properly in your estate plan.
Another possibility is establishing a scholarship fund at an Orthodox seminary or primary school. Even a small gift can make a difference in the life of one scholar.
Rather than a percentage, which can take more time to distribute while assets are appraised and sold, consider gifting a specific asset, which may be transferred much sooner depending on the law in your jurisdiction.
Other Orthodox charities you might consider:
https://iocc.org/gifts-of-love
Endowment fund for widowed clergy wives : https://antiochian.org/regulararticle/1815
NOTE : The website may not be working as it is due to under construction
Orthodox Estate Planning 