Here is a list of current known airlines that have grounded their Boeing 737-8 MAX 8 aircraft or have been ordered by their respective countries to ground their aircraft.
Aerolineas Argentinas – 5 Boeing 737-8 MAX 8 aircraft grounded
AeroMexico – 6 Boeing 737-8 aircraft grounded

Air Canada – Canada closed its airspace to all MAX aircraft on March 13, 2019. 24 Boeing 737-8 MAX 8s grounded on March 13, 2019
Air China – 15 Boeing 737-8 MAX 8 aircraft grounded
Air Italy – 3 Boeing 737-8 MAX 8 aircraft grounded on March 12, 2019
American Airlines – FAA ordered all 24 Boeing 737-8 MAX 8s to be grounded on March 13, 2019.
Cayman Airways – 2 Boeing 737-8 MAX 8 aircraft grounded
China Eastern Airlines – 3 Boeing 737-8 MAX 8 aircraft grounded
China Southern Airlines – 24 Boeing 737-8 MAX 8 aircraft grounded
Comair (British Airways franchise) – 1 Boeing 737-8 MAX 8 aircraft grounded

Copa Airlines – 6 Boeing 737-9 MAX 9 aircraft grounded on March 13, 2019
Enter Air – 2 Boeing 737-8 MAX 8 aircraft grounded
Easter Jet – 2 Boeing 737-8 MAX 8 aircraft to be grounded on March 13, 2019

Enter Air – 2 Boeing 737-8 MAX 8 aircraft are currently not operating
Ethiopian Airlines – Remaining 4 Boeing 737-8 MAX 8 aircraft grounded

Fiji Airways – 2 Boeing 737-8 MAX 8 aircraft affectively grounded as Australia bans the aircraft type from Australian skies (except the New Zealand market). Fiji later banned.
flydubai – 11 Boeing 737-8 MAX 8s and 3 Boeing 737-9 MAX 9s grounded on March 12, 2019
Fuzhou Airlines – 2 Boeing 737-8 MAX 8 aircraft ground
Garuda Indonesia – 1 Boeing 737-8 MAX 8 grounded
Gol Transportes Aéreos – 7 Boeing 737-8 MAX 8 are grounded
Hainan Airlines – 11 Boeing 737-8 MAX 8 aircraft grounded
Icelandair – 3 Boeing 737-8 MAX 8 aircraft grounded on March 12, 2019
Jet Airways – 8 Boeing 737-8 MAX 8 aircraft are stored

Kunming Airlines – 2 Boeing 737-8 MAX 8 aircraft grounded
Lion Air – 10 Boeing 737-8 MAX 8 aircraft grounded
LOT Polish Airlines – 5 Boeing 737-8 MAX 8 aircraft grounded on March 12, 2019
Lucky Air – 3 Boeing 737-8 MAX 8 aircraft grounded

Mongolian Airlines (MIAT) – 1 Boeing 737-8 MAX 8 aircraft grounded
Norwegian – 18 Boeing 737-8 MAX 8 aircraft were grounded on March 12, 2019
OKAir (Okay Airways) – 1 Boeing 737-8 MAX 8 aircraft grounded

Oman Air – 5 Boeing 737-8 MAX 8 aircraft grounded
Royal Air Maroc – 2 Boeing 737-8 MAX 8 aircraft grounded
Shandong Airlines – 6 Boeing 737-8 aircraft grounded
Shanghai Airlines – 11 Boeing 737-8 MAX 8 aircraft grounded
Shenzhen Airlines – 5 Boeing 737-8 aircraft grounded
SilkAir – 5 Boeing 737-8 MAX 8 aircraft grounded
Smartwings – 7 Boeing 737-8 MAX 8 aircraft were grounded on March 12, 2019
Southwest Airlines – FAA ordered all 34 Boeing 737-8 MAX 8s to be grounded on March 13, 2019.
SpiceJet – 13 Boeing 737-8 MAX 8 aircraft were grounded on March 12, 2019
Sunwing Airlines – 4 Boeing 737-8 MAX 8 aircraft we’re grounded on March 13, 2019
S7 Airlines – 2 Boeing 737 MAX 8 aircraft were grounded on March 12, 2019
Thai Lion Air – 3 Boeing 737-9 MAX 9 aircraft were grounded on March 13, 2019
TUI Airlines Belgium – 4 Boeing 737-8 MAX 8 aircraft were grounded on March 12, 2019
TUI Airways UK – 5 Boeing 737-8 MAX 8 aircraft were grounded on March 12, 2019
TUI fly Netherlands – 3 Boeing 737-8 MAX 8 aircraft grounded on March 12, 2019
TUI fly Nordic – 2 Boeing 737-8 MAX 8 aircraft grounded on March 12, 2019
Turkish Airlines – 11 Boeing 737-8 MAX 8s and one Boeing 737-9 MAX 9 ground on March 13.
United Airlines – FAA ordered all 14 Boeing 737-9 MAX 9s to be grounded on March 13, 2019.
WestJet – Canada closed its airspace to all MAX aircraft on March 13, 2019. 13 Boeing 737-8 MAX 8 grounded on March 13, 2019.
Xiamen Air – 10 Boeing 737-8 MAX 8 aircraft grounded

9air.com (Jiu Yuan Airlines) – 1 737-8 MAX 8 aircraft grounded
In total, we currently show around 360 Boeing 737 MAX 8 aircraft are now being impacted or grounded. In addition, the affected airlines also have over 800 aircraft on order from Boeing and various leasing companies.
Note: We now believe that all Boeing 737 aircraft have been grounded worldwide except for test flights (by Boeing) or ferry flights without passengers. This list will not longer be maintained.
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