In the first week
Start by notifying all the members of your immediate family and relatives, along with friends. Don't forget to contact any appropriate clergy or spiritual counselor. Then alert financial professionals who may have had dealings with the deceased. This should include contacting the company that manages funeral benefits for the deceased, as well as investment advisors and insurers.
Next, make sure any dependents of the deceased will still have care, and immediately arrange for the care of any pets. Prepare an obituary and have it published, and begin arrangements with a funeral home.
It’s also important to start gathering documents, such as a will or trust, insurance policies and any document detailing the funeral wishes of the deceased. Ask for several copies of the death certificate. You may need these for various companies and organizations.
By the end of the first month
Get documentation that will allow you to make decisions on behalf of the deceased.
You may want to see to any loans, bills, tax accounts and any other ongoing financial obligations of the deceased. Even though some of these will be closed out, keep the accounts current for now. There may be money due from the deceased’s employer that can help pay these bills, so contact the relevant person or company about paychecks and benefits. If the deceased was a partner in business, contact them regarding ownership rights and amounts due. Contact any financial institutions that hold investment accounts in the deceased's name to find out if a beneficiary was named, and call or write to all relevant credit card companies and ask to close the accounts.
If there is a will or trust, you may want to consult an attorney for review. Also, you can bring the document to your local courthouse to find out what further action you will need to take.
You will need to notify the Social Security Administration, Medicare, Medicaid and possibly the Veteran’s Administration.
You may want to consider contacting an accountant to prepare final tax returns of the deceased's estate. Make sure to file those returns — it's required by law.